Rear End Swap 7-1/4" to 8-1/4"

I have a 8 1/4 waiting in my garage to get put it. I still have no back plates at all so that is the only thing I am curious about. I was told I could go to any junkyard and get a set of 10x2.5 drums pretty easy. Did you just use sandpaper to strip down the rear end before painting it becuase I am working on mine now and the paper is wearing me out.