Well, in theory the entry in the config.ini of CamHack should be
FOVY=0.2777777
calculated (4/3) / (XRes / YRes) = 0.2777777
according to the data you supplied.
I tried just for fun with 1920x432 ==> FOVY=0.3 this actually did work. I have of course one monitor only.
The new FixUp 1.4 does the job right also, at least for the animations and the objects when driving.
As expected, the menues get distorted (stretched) ugly.
Surely you will have to use the SoftTH software to get everything right. I guess there should be a user here having such a configuration.