Changelog for Top Gear Complete Collection v2.0 (TGUP v5.0) - released September 2020. Note that major changes are placed at the top of each sub-list by hierarchy; their items are then ordered chronologically. Very special thanks to Jay Sutherland and Prateek Joshi for all their help and assistance, in addition to anyone else who contributed to the production of this pack.

Changes from TGCC v1.0:

Documentation:
Added copy of Top Gear episode guide based on personal opinion for those new to the series; feel free to share and critique
Added Excel guide for Rally Report
Added Excel guide for Best of Top Gear compilations; 75% of them have now been located, including all of those which aired from 2006 onwards
Updated Excel guide for Old Top Gear
Updated Demands & Requests
Slightly amended Rally Report episode guide text file; number of episodes was previously incorrect
Added document concerning soundtrack coverage of Series 1
Added version history, sneak-peak at when future versions will release and what they will contain

Home Videos:
3 hour long "Best of British" Blu-Ray added to "Compilation DVDs", in addition to "The Best of Series 3 & 4", thanks to AliciaTywysoges for these
Alternate version of the Winter Olympics home video added to this folder too
DVD releases of the Polar Special, Bolivia Special, Romania Road Trip, East Coast Road Trip, Middle East Special, Albania Road Trip, India Special, Supercars Across Italy and Africa Special all replaced with their corresponding Blu-Ray rips from the QxR team, compression added via Handbrake
Blu-Ray rips of the Patagonia Special and Australia Road Trip added, again thanks to QxR; subtitled as "Great Adventures Vol. X" even though they were never released as such, simply for chronology
Added Tiff Needell's 20 Cars That Changed The World, crossing off a demand (thanks Phat_J!)
Added Jeremy Clarkson's Motorsport Mayhem from Prateek's DVD rip, subtitled it as "#0" in his home video series
Also added Tiff Needell's equivalent 2001 DVD release, Dangerzone, from Phat_J's collection
Footage from Richard Hammond's Stunt Challenge added to its own directory due to its uniqueness (thanks again Prateek!)
Added the other interactive DVD to its own directory in the final days, due to its sudden submission to Archive.org
720p version of Top Gear At The Movies replaced with 1080p Blu-Ray rip, which is 545MB smaller than the former once optimized
Direct Blu-Ray rips of Burma Special and Clarkson's Italian Job sourced for v1.0 of the pack have been optimized with Handbrake, saving 41 GB
The BTS for The Italian Job has also been compressed from its original 10GB down to 2GB
The other three extras associated with The Italian Job have also been compressed, saving another 624 MB
"Top Gear - Greatest Movie Chases Ever" and "Top Gear - Winter Olympics Special" have been moved from the root directory to the "Compilation DVDs" folder
"Berry on Bikes" has been renamed to "Steve Berry" so that Clarkson's videos appear first in the root directory
All of Clarkson's home videos have been renamed so that they are presented in chronological, rather than alphabetical order

Old TG:
New program added: Perpetual Motion in "Other Stuff" folder (as it was advertised at the end of Top Gear; 12 episodes total)
New program added to Clarkson Series folder: Extreme Machines, along with a lot of footage/clips (special thanks to Prateek for all of these)
All of Series 4, the Series 9 Special and S12E07 of Rally Report added to respective folder
Episode 1 of Clarkson's Car Years found and added, in addition to extended original BBC2 airings of episodes 2 and 5, and a higher quality version of episode 3 (thanks to Phat_J); all have been renamed to have their original titles
Final episode of Clarkson's Speed added (thanks to Prateek), in addition to each episode being renamed to contain their original titles
DVD rip of Speed compilation has also been added; found via eMule
Full episode of Top Gear GTi added to the "GTi" folder (thanks to YouTube user gud6y; also responsible for the motor show-related additions of the main show)
7 and a half hours' worth of Top Gear Motorsport content added, including 11 complete episodes (mostly rally-related)
One whole Series 17 episode added to the "1984 - 1988" folder; Episode 7 (thanks to YouTube user Redline Ste, same applies below)
Large fragment of Series 19 episode added to the "1984 - 1988" folder; Episode 1
Two-part Motor Show '90 special added to the "1990" folder
Motorfair '91 special added to the "1991" folder
Motor Show '92 special added to the "1992" folder
Low quality recording of S30E11 removed, replaced with higher quality version in the "1993" folder
S32E05 clip removed from "Segments", replaced with full episode
Motor Show '94 special added to the "1994" folder
S33E11 clip removed from "Segments", replaced with full episode in the "1995" folder
S35E02 removed from "Episodes" due to incorrect second segment; Vauxhall Vectra clip moved to "Segments" folder
Partial recording of S36E11 removed, replaced with full episode in the "1996" folder
Series 38 episode added to the "1997" folder; Episode 10
Added BBC2 airing of the 1997 London Motor Show, renamed shorter cut to "(BBC World Version)"
Three whole Series 44 episodes added to the "2000" folder; Episodes 3, 5 and 6
Motor Show 2000 special added to the "2000" folder
Noel Edmonds two-part special feature "Noel's Le Mans Dream" added to "Other Stuff" folder
Driven episode for 10/11/1998 added to "Other Stuff" folder, the only surviving complete episode of Driven with James May as host
Final episode of Clarkson's talk show added to "Other Stuff" folder
2002 BBC2 documentary "Cobra Ferrari Wars" added to "Other Stuff" folder; not really related to Top Gear but a rare find and an interesting watch regardless
Sinclair C5 clip from S15E02 added to "Segments" folder
Higher quality Lotus Esprit clip from S30E10 added to "Segments" folder, since the rest of the episode isn't worth updating
Vauxhall Omega segment from S31E02 added to "Segments" folder
Two clips from Youtube user minsrg4 added to the "Segments" folder; Suzuki Bandit and Budget Hot Hatches, from S34E02 and S40E06 respectively. The latter was removed from the BBC World airing of the episode.
Higher resolution version of the SAAB rally car segment from S35E10 discovered via eMule and added
Porsche 911 Turbo segment from S43E18 discovered via eMule and added
Ferrari Festival clip from S44E11 discovered via eMule and added
S44E13's Noble M12 GTO clip source file found, replacing the lower quality YT rip
Lamborghini Diablo clip from the 2000 Top Gear Awards special discovered via eMule and added
Mercedes-Benz SL500 clip from the 36th and final episode of Series 45 located and added
Clip focusing on sports convertibles' filename corrected from "S45E14" to "S45E13"
09/03/1999 episode of Top Gear Take 2 found and added to its respective folder
S01E03 of The Car's The Star replaced with full episode
Second half of S02E02 of The Car's The Star bolted on to the higher-quality first half; episode now complete
S04E01 of The Car's The Star replaced with master quality iPlayer rip
1998's "100 Years of the Land Speed Record" episode and Series 45's "Car Park Getaway Clip" replaced with slightly higher quality versions

TG 2002:
(Note: This part of the list may be inaccurate. I'm aware of stuff like the Patrick Kielty interview and the Great Britons episode, but since they're not directly related to Top Gear, have declined to mention them.)

Every main episode now has subtitles, Series 1 also has soundtracks and chapters for ease of access and navigation
First three MTOD series re-downloaded from scratch via the source files and upscaled by Phat_J rather than captured from OBS, in addition to accurate subtitle files also extracted from these versions; QxR are to thank for the latter and the overall idea; SBS rips of Series 1 & 2 deleted, saving 38.3 GB, due to the quality that the upscaled MTOD rip provides in addition to the lack of onscreen graphics - redownload from v1.0 if you preferred these
Series 4 & 5 have also received upscaling via GigaPixel Video Enhance as the MTOD cuts are especially egregious, removing 10 - 15 minutes from each episode on average and there aren't any alternate anglophonic airings available anywhere, barring the badly cut Dave versions
The first four episodes of Series 6 have been replaced with upscaled MTOD source files and BBC2 audio relaid (as they weren't cut); the other 7 are BBC Three re-airings from late 2007
Series 7, 8 & 9 episodes replaced with clearer 2007 - 2008 BBC Three re-airings from [CLASSIFIED SOURCE], apart from S07E05, which also comes from MTOD, and S09E01, which is upscaled from the Scene release
Series 10 - 13 have also received the same treatment as 7 - 9, alternating between BBC2 original airings and BBC3 re-airings, all of which are in their original broadcast resolution
Series 14 - 21 have all been individually de-interlaced/re-encoded to .mkv at 19.5 RF for the most part, with filesizes of around 1.5 GB less on average and sync'ed subtitles (re-download V1.0 if you prefer the uncompressed 50 FPS .ts)
In addition, the Polar Special has been re-encoded to 2.93 GB vs. its previous 7.07 GB
All eight episodes of Top Gear Top 40 added to the "Bonus Features" of Series 17
Both episodes of Top Gear: Top Fails added to the "Bonus Features" of Series 18
All eight episodes of Top Gear: Ambitious But Rubbish added to the "Bonus Features" of Series 21
New folder added: HQ Clips (2003 - 2009); several hours of master-quality 576i footage from the first 13 series ripped directly from the official Top Gear website, mainly challenges and car comparisons
Further rips from the website have also been made and placed within the series of which they are most relevant, mainly pertaining to the show's magazine.
Extended 83-minute cut of the Vietnam Special produced by Phat_J of FinalGear - added to the "Bonus Features" of Series 12 due to the lack of an official BBC Directors' Cut
The Holy Grail: Original 20/10/2002 airing of S01E01 located - added to "Bonus Features" of Series 1 and its audio has been made the default channel for the episode
"Extended" version of S01E10 created by Phat_J using footage from the BBC Prime airing
BBC World airing for the first 11 minutes of S01E02 (Focus RS test) located - added to "Bonus Features" and its audio has been made the default channel for the episode; most of the episode now has its original soundtrack restored
BBC World airing of S01E05 located - added to "Bonus Features" and its audio has been made the default channel, along with a couple other clips; most of the original episode audio is now restored
15-minute long airing of S01E05/S01E06 (it appears they mixed episodes together at certain points) added to "Bonus Features"; contains an elusive clip of the SL55 AMG with Coldplay's "Clocks"
UK Horizons airing of S01E09 located - once more, added to "Bonus Features" and the audio has been made the default channel for the episode in the main directory; S01E03 has been renamed to (UKTV Airing) rather than (2003 UKTV Airing)
Missing footage from S01E10 recovered and added to the "Bonus Features" of Series 1; original Lotus Esprit segment with Bond-themed lead-in; now all footage for the first series is available in some form
Trailer for Series 1 and episode trailer for S01E02 located and added to the "Bonus Features" of Series 1
2002 Birmingham Motor Show special added to the "Bonus Features" of Series 1
Original Jabba clip of Zonda vs. Murci╬ślago added to the "Bonus Features" of Series 1; this is basically the "Genesis" of Top Gear clip sharing if the Needell era isn't taken into consideration
Clip of Vanquish vs. 575M added to the "Bonus Features" of Series 1; this is the highest available quality of any UK Horizons airing of Top Gear
BBC World clip of the Honda NSX Type-R (along with the original song played during Stig's power lap) added to the "Bonus Features" of Series 1; most of S01E06 now has its original soundtrack restored as a result
Clip of the hot hatch comparison test from the original BBC2 airing of S01E09 has been added to the "Bonus Features" of Series 1
TVR T350C test from the original BBC2 airing of S01E10 have been added to the "Bonus Features" of Series 1; the former appears to preserve a sound glitch that occurred during its maiden airing
Two more "Greatest Car" segments located; Stuart Hall on the Rolls-Royce Silver Cloud and James May on the Citroen DS; added to the "Bonus Features" of Series 2
Clip of the M3 vs. S4 comparison test from the original BBC2 airing of S02E02 has been added to the "Bonus Features" of Series 2
Clip of the nitrous-injected XJS from the original BBC2 airing of S02E03 has been added to the "Bonus Features" of Series 2, alongside hints of a scene deleted from the MTOD version
BBC World version of S02E07 has been added to the "Bonus Features" of Series 2
First 10 minutes of the original BBC2 airing of S02E10 has been added to the "Bonus Features" of Series 2
Original BBC2 airings of S03E03 and S03E09 have been found, added to the "Bonus Features" of Series 3
Renamed "Top Gear - Best of Series 3 [2004.01.25]" to "...[2003.12.20]", as that is the original airdate
Best of Top Gear from 13/01/2004 (in reality an abridged version of S03E03) located and added to the "Bonus Features" of Series 3
Outtake TV clip featuring Top Gear team added to the "Bonus Features" of Series 3
Handmade subtitles for S4 - S5, using the MTOD versions as a base
Spyker C8 clip from the American Discovery airings of Top Gear found and added to the "Bonus Features" of Series 5, along with one half-episode: Episode 7; note the completely unique US studio scenes filmed in February 2005, the first time the trio set foot in America
Trailer for Series 6 located and added to the "Bonus Features" of Series 6
Dave airings of two early 2006 "Best of" compilations (The Supercars and The Special Guests) obtained and added to the "Bonus Features" of Series 7
Trailer for the Winter Olympics Special found in its original broadcast resolution and quality; added to the "Bonus Features" of Series 7
Best of Top Gear compilation for the 27/01/2008 located and added to the "Bonus Features" of Series 10
All known trailers from Series 10 onwards located and added to their respective folders, with many lower quality trailers removed
Low quality rip of Richard Hammond Meets Evel Knievel replaced with 576i BBC Three recording
Top Ground Gear Force in much higher quality and with charity interruptions removed, added to the "Bonus Features" of Series 10, along with a lower quality alternate intro from its re-airing ten days later
Added the Best of Top Gear compilation for 01/02/2009 to the "Bonus Features" of Series 12
Renamed "Top Gear - Best of Series 11 & 12 [2009.03.15]" to "...[2009.01.01]", as that is the original airdate
Sixty Minutes Australia "Rev Heads" feature added to the "Bonus Features" of Series 11
2009 BBC2 documentary "The Car Show" found and added to the "Bonus Features" of Series 12
"Fire Up The Quattro" charity skit added to the "Bonus Features" of Series 12
Found and located all four "Best of Top Gear" specials for Series 13 - 14; added to Series 14's "Bonus Features" folder
Channel 4's "Greatest TV Show of the Noughties" special added to the "Bonus Features" of Series 14 (take a wild guess as to which television program won the coveted #1 spot)
2010 BBC Four documentary "Hammond Meets Moss" added to the "Bonus Features" of Series 15
Second of two Best of Series 15 compilations found and added to the "Bonus Features" of Series 15
CBS 60 Minutes Top Gear feature added to the "Bonus Features" of Series 15
Second of two Best of Series 19 compilations located and added to that series' "Bonus Features"
Redubbed TV rip of Festival Sydney replaced with 1080p Prime/MTOD rip, once more thanks to QxR
All four Best of Series 20 - 21 compilations added to the "Bonus Features" of their respective series
The three remaining Best of Series 22 compilations have been added to the "Bonus Features" of their respective series