lots of folks are running 8.8's in a-bodies. they're cheap and plentiful, parts are easy, minor surgery to make fit and you get disc brakes. a lot of them came stock with LSD's and factory gears up to 4.10
if i was going for a brand new rear end, a 9" is a no brainer. you can get a custom built unit with discs and whatever ratio LSD you want for damn near half of what you'd have into 8.75 piece. if weight wasn't a concern and you're planning on putting down big ugly power and don't want to break anything, a dana built to spec by dr. diff is the answer there.
