8 1/4 rear end

[eastvan52]

looking at swapping my 7 1/4 diff for an 8 1/4 - its a 75 dart swinger - what are the measurements to make sure that i get the right one -

 

[mrhollywood]

I believe they are all the same for the A-bodies,but the drive shaft length is different when switching from the 7 1/4 to 8 1/4. just get the drive shaft from the same car as the rearend and you're good to go.