8 3/4" rear question

Some thing to also keep in the back of your mind, original "A" body units command top dollar. Finding one in a junk yard is slim to none. One possibility would be to pull a "C" body unit or a pick up truck unit; these are not as in demand as an "A" body unit. Send the housing out to be narrowed to "A" body width with new spring perches, after market axles with green bearings and bolt it in.

It's an idea.