A-body 8-3/4 axles bbp

It does mater. It maters where the bearing is. You cannot just buy on any backing plate you want. They could be set up for 11by 2 witch is common for c bodies. If they are set up for 10 x 2.5 I would take them.let me know shipping 06410
thanks
I believe the backing plate determines which brack drum you use
That is how a B-body works anyway