Sorry, no fancy video today folks. I honestly couldn't be bothered.
Patch for the US version of MC3: Remix (Tick Enable Widescreen Patches in PCSX2 to fix 3D rendering):
drive.google.com/file/d/1QYbvBzTaF7c8y88woe9wj8f0oWmbYVgN/view?usp=sharing
To call this a fix would be quite disingenuous. It more-so is a workaround than it is an actual fix. MC3s HUD size is dependant on the game's internal resolution (as are the other R* San Diego AGE games, see MC2 PC).
Therefore, I simply instructed the game to run at a higher internal res (640x480 as opposed to 512x448). This meant the UI properly scaled to 16:9 now. There were a lot of upscaling bugs I had to go and manually fix though.
Do NOT use this patch on actual hardware, as it most likely will just break your game. PCSX2s software mode also becomes unuseable.
There still are issues - mainly, headlights are cut off near the right side of the screen. This bug also affected other post processing effects, but those I had managed to fix. Spent a lot of time looking into the headlights though and couldn't find anything worthwile. However, I personally got used to it pretty quickly. The text in the pause menu also is misaligned, but that probably can be solved without too much effort. Will update this if and when I do.
Lastly, on newer PCSX2 builds, whenever you go over 25 mph for the first time during a game session, the emulator might start using up a shitton of VRAM for a second. It doesn't occur on older non-Qt PCSX2 builds, so I really don't know what that's all about.
I wish there was a better way of going about this, but MC3s HUD code sucks, and fixing it manually might just be outside of my wheelhouse. I spent a grueling amount of hours looking into HUD scaling independant of internal res, all resulting in mere futility. I'd rather not waste any more time on this. So yeah, definitely use this at your own risk - but all things considered, I would rather have a nice looking UI than not.