8.75 for my A-body

Ignorant? No problem, we were all there once and I still count myself as "Dumb ***", so, your in good company. ;)

The actual width I can not remember off hand, but in the future, the MoPar Chassis book as this and loads of info. The engines book is a good one to, though narrowed veiwed since it is only a MoPar product they deal with. Excellent book(s) though.

You can get the axle ends new from Mancini and axles from alot of places normal to racing/hot rodding. Like, Strange, Yukon, Moser, etc.....
I beileve theres an ongoing issue at mancini with there axles.