wonky rear end

[dan_kitty]

hi, Ive been having aproblem with my b4's rear end. when looking at the car from the back the transmission seems to be at a slight angle compared to the chassis which would explain why it handles like poo coming out of corners (back spins round). I have tried replacing most of the parts ie: motor plate, top plate, bottom plate, hinge pins yet still appear to have the problem. Before I change the chassis is there anything im missing?
Is it possible for the chassis to be warped?

cheers in advance
dan