I am replacing my 305 with a 383. Its not finished but about half way so I am looking at posi units. I have been looking at several different posi units and trying to learn as much as possible. Ideally I would like to replace my whole rear end and get a new/used one with the right axles and rear disc breaks, so that’s what I am looking for. One of my buddies knows someone selling a Caprice that was a taxi with around 150,xxx miles on it and said I could take the rear end, so my question is will the rear end fit in my 87 trans? The only concern I could see would be axle length from possibly having a wider wheelbase. Or do I have to get one out of a f-body?

 

Well aside from probably being too wide (personally don't know what width the Caprice is) you'll have to relocate the shock mounts, spring mounts, lower trailing arm mounts, and figure out a way to hook up your torque arm. You'd be money and time ahead by just keeping up the search for a rear that will bolt right in. I ended up buying 2 rears to make the one I wanted, now I'm getting a Ford 9" so it was kind of a waste but not at the time. bought a 3.08 with a posi and drum brakes, bought a rear with 3.42 1 legger w/ disc brakes. Took the posi unit out of the 3.08, bought a spacer and installed it into the 3.42. Total cost for everything $175.00 Now I need 4.11's and I'm sure the heck not putting them in a 7.5" rear for my own personal peice of mind.