I need some info on these rears, how strong are they? Avalibilty of parts? Are they stronger then a 12 bolt? I know they came in the 3rd gen slp firehawks, and my friend has an 89 trans am, engine builder says 550 horsepower n/a(at the crank, not rwhp), he has turbo 400 tranny, with a 3500 stall, and steel driveshaft, he plans on nitrous down the line. He can pick it up for 800 bucks plus trade for a stock 2.73 10 bolt, the mileage is unknown, gears are 3.54s, sound like a decent deal? Will it handle the kind of power hes making with slicks?