Is that 52 5/8 to the inside of the flange or outside of the flange. I have checked on several websites and get different numbers. I believe the 8 1/4 from 73 up are a different length. The mopar website states the 66-72 A body rear at 52 13/64 while the 70/71 A body rear is 52 37/64 which is 3/8 " difference. Confused yet; I am. Can anyone clarify the correct measurement and where is it taken from? Thanks