Are S10's that weak? I wouldn't think so, seems a 4.3L put out more torque that a 283. Torque snapped both(on seperate occasions) rear axles on my task force with a well worn 283. Looking at this s10 rear it looks like my Nova rear end I beat the crap out of with no problems. Worth a little research I guess. The s10 rear end I have now has 200k on it and came from an obviously abused truck. Still seems pretty tight. Aren't they the same as the 10 bolts that have been around in GM's for years? I know they come in three flavors and the 8.5 inchers are what the drag racers love next to their 12 bolts and Dana 60. A lot of dirt trackers run the 8.2's and 7.5 modified for positive retention. 7.5's came in:
'75-'79 Omega
'82- up Camaro/Firebird
'82- up S-10/S-15
'76-'79 Skylark
'77-'90 Fullsize Olds/Buick/Pont
'77-'96 Fullsize Chevy
'78-'81 Century/Phoenix/Ventura
'78-'87 Cutlass/Grand Prix
'78-'87 Monte Carlo/Regal

Most of these beasts make more torque that a 283, some a lot more.

Jim

Good luck with your project!