I have a 64 malibu with a 10 bolt rearend. I want swap in either a 12 bolt or the larger 8.5 10 bolt. Does anyone know which rearends will fit, other than 64-65 chevelles and elcamino's. Hopefully without to much modification.

Any '64-67 Chevelle rear will fit. There are some minor spring perch differences, but I'd suggest a '65-67 12 bolt. If you are junkyarding or swap meeting, the backing plate to backing plate dimension on the '65-67 is 54", 68-72 is 55". The late rear will look weird & give you tire clearance trouble.

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