ok, ive been reading up on here as much as i can find, and i still missed something. i was cursed with the borg warner nine bolt with 2.77s in my 86 t/a, and it has disc brakes. i am looking at putting a ten bolt in it, but theres a couple of questions i still have. From what i understand, the calipers from the bg will bolt up to a nine bolt as long as the backing plates are 89-92? how are they different if its an earlier model? is there any way to convert a drum brake ten bolt over to the disk brakes from the nine bolt? and which ten bolt is better to get, the 7.5 or the 7.625. as far as i can tell, they are virtually identical inside, correct? any help would be greatly appreciated!

huh? a BW is a 9bolt. if what you ment was will the 9 bolt calipers fit the 10 bolt then, yes. but, you NEED the correct backing plates. so you are going to put a 10 bolt in the 86 right? then you need 10 bolt mounting brackets for the old iron calipers. the bolt holes on the axle housing are slighlty off.

yes, you can take a drum 10 bolt and switch to disk just do a search. you have to cut the mounting flange