ChryCorp Passenger Car Rear Axle Dimensions and ID: 1962 to 1989

That listing needs to go in the garbage. ol Frank did some pretty crappy research. A hollander manual could have been used, but, I guess not!

A 8.75 flange to flange are 52 5/8. Where that 51.40 number comes from is beyond me.

62-70 B rears ARE NOT the same length for those years.

That moparts link is the best for 8.75 rears.