new 8 3/4 length?

Hey guys, I just picked up an 8 3/4 and I am planning on shortening it because I believe it is an e body rear. My question is should I just get it shortened to stock a body length? I am not going to put any overly large tires so i figure that stock would probably be best. Also i plan on putting disk brakes on all 4, so I don't know if this makes any difference. By the way this is going in a '69 dart. Anyone done this before? Anyone use any other lengths? Thanks