If the backing plates came off of a Challenger, they will work fine with Dr. Diff's BBP axles for an A body rear end. 10-4 on the driveshaft. I wasn't sure if a 727 may be a future possibility is why I threw that part in. A good 904 works better in a hot rod anyway! I've used the flip flop u joint before with no problems or vibration if you just want to shorten the existing driveshaft for now to not have to pop for a whole new one right away. Hope it turns out really good for you!
:thumbsup: :thumbsup:
