Early A Body Rear Swap

Thinking about swapping out the stock 7 1/4 rear in my 1964 Valiant for a Dana 60 out of a 70s E body. I Googled the flange to flange difference, and it came to around 6 inches wider. In my mind, I'm thinking-OK, that amounts to 3 inches on either side, so just buy wheels with the proper offset and all should be good. Google also informed me about the driveshaft to rear centerline differences of around 2 inches, but I have no clue what that is referring to. I'm also aware that the spring...

Early A Body Rear Swap
Author: valiant64