spring pad location

Is the housing 52 5/8 inches flange to flange where the axles bolt in? That's factory A body 8 3/4 length. Someone may have moved the spring perches out a half inch on each side to put that rearend in a B body sometime in the last 60 or so years. What's weird is, I have one with that exact same situation I'm working on right now. Original A body 8 3/4 housing with the obviously moved perches set at 44". It had also shucked the ring gear out and cracked the rear bubble of the housing. I was welding that up yesterday and noticed the perches had been rewelded, so I measured them. 44"! I just bought some new perches from another member here to weld on at 42" to move my springs in a half inch on my 65 Barracuda, so I was gonna cut the old ones off anyway.

To answer your question, the housing will go into the car and sit on the springs being a half inch too wide on each side, but it splays the springs out and I would imagine it would eat the bushings up quicker. I helped a friend put a B body Dana 60 in a 73 Dart Sport when we were teenagers, and we bolted it in that way. It worked good and didn't drive funny, but now that I know better, I'd move the spring perches to where they need to be to keep everything straight.