Yes, I have used OpenIV's search to look through all of the handling.meta files. There is only one instance for the brawler. I am going to look through them all Manually I have a hunch that it could be a typo (or even a rename) in the files.... this might take a while :C
EDIT: Not as long as I thought, but I found nothing. I can alter the model from mplux2 to add a spoiler onto a rear bumper and that shows up. It could be that the fBrakeForce value is not enough to fix the problem. I will keep digging.
EDIT 2: ' Well changed the fInitialDriveMaxFlatVel to a much higher number and yeah it goes faster. So it is a traction problem not a wrong file being called problem.