The rear end, PJJ 01574, is from a 1991 3/4 ton Chev. conventional cab, 4 w/d, p/u, non locker, with a 9.5" ring gear, according to the wrecking yard I bought it from. I called Patrick's who suggested calling the wrecking yard because they have ALL the info on parts. And, I figured if they gave me the wrong info the first time, they could help me out. They were happy to look up the info. Yeh, now I know what I'm buying parts for.