it is best to get new axles and backing plates to reap the full benefits of the big bolt pattern what are the a body brakes 1 3/4 wide? i forget. you should go to 10 x 2.5 drums or even better 11 x 2.5 drums. buy a whole assemble so you get the right parts. either new axles or a set of c body axles resplined. it doesn tmake any sense to me to re drill a body drums. they are small to begin with and if you need to replace them, they arent the easiest to find, you will have to have the new set re drilled. the stupidest part of that route, no wheel will be hub centric because you have that tiny hub from the 4" bolt pattern.