What is going on 8 3/4 axles too long?

I needed to change the axle seal on my 66 barracuda rear end. Put it together and the drivers side axle is sticking out 1/2 inch. Someone modified the backing plates by soldering bolts on it to push out the break pads. I have tried to adjust it in with no success. Do I need a bigger hammer? Shorter axles? Thanks in advance