changing rear axle from sbp to lbp

I've always heard if you go with aftermarket axles that the offset is different than stack a-body axles therefore one of two things need to be changed .
1 the stock a-body drums need two be turned for clearance along the edge
that interfaces with the backing plate or 2 the backing plates and drums will need to be changed to those like on b/e bodys . Because most aftermarket manufacturers use the larger cars offset and don't change any of the machining when the produce the bbp a-body axles. As they've become aware of that they may have changed that practice. When I changed the axles in My Dart I aquired a B-body 8 1/4 axle with 10" X 2 1/2" brakes everything fit perfect! I dod have an extra set of backing plates if your interested I have the drums too but They're pretty scored up not sure if they could be turned .
Let Me know if your interested. Not in dfw area n.Cal. So you'd have to pay for shipping...