Auto Parts: Chevy 10 bolt pos trac rear end, limited slip differential, salvage yard

Question
How do I tell if I have a 8.50 or a8.25 acrrier. Would either one go in my housing and are axles the same. I have a1970 camaro that needs a gear and a 1988 iroc that needs a carrier..

Answer
    The 1970 has an 8.25 carrier.  They switched to 8.5 in 1973.  A good used carrier shouldn't cost that much from a salvage yard.  If you've got enough horsepower, now would be the time to fit lower gears and limited-slip differential.  Even if you don't have a modified engine, you'd be surprised what a difference a set of 3.73 gears will make.