Bacon2890: Old post but thought I'd post here. I've not tested it but I've found the file at least..
Field of view (FOV)
Go to the configuration file(s) location. (example - D:\GOG\SWAT 4\Content\System) It's located in the system folder
Open SWATPawn. ini (make the game has been launched at least once).
Go to class [SwatGame. SwatPawn] .
In this section adjust line FirstPersonFOV= .
Change from 85.0 to the desired value.
Edit: Confirmed it works great.
I'm using 2560x1440p with a 110 FOV (but thats up to the player how they like it) 120 is fairly good but if you have your weapon on another officer the player aims his gun down and it was showing the back of the weapon that doesn't exist (more or less). So I did 110 and found that worked for me on this res.
Edit 2: Forgot to mention this is a full vanilla version of the game. Just edited the res like I've always done (Juandice23's comment above me tells you how to) you can also edit the fps should you be running a monitor higher than 60Hz.
I am not really sure how you managed to make it work great, but for me the image is really deformed and stretched unrealistically.
Also that 110 POV, only make me see a little from behind but still stretched and deformed, but with 110 degrees I can also see where the hands and weapons drawind ends, making the game even more akward to play.