No, 4wd, 86-95 rear housings have perches in the exact same spot as pre-86 housings. If you find a truck with that, you should be able to bolt it right up. Get everything you can with it, drum to drum, including axles, brakes lines, e brake cable, and so on. If the brake cable is not with it, you will just have to extend yours a bit. That is all. Oh and yes you can bolt up the 3rd you currently have.