It would seem to me that the S-10 would be a little light duty for that "tank" you want to put them in. A Camaro/Nova/Monti clip would be much better in your case and any of the GM V8 rears that are leaf spring and the correct width should work just fine. They would be strong enough to handle a good sized V8 as well.
Just a thought, Buick Regal, say `74 to 88 subframes are two inches narrower at the a-arms than the camaro/nova which will open up wider wheel choices, and small block chevys will bolt right up into them, having found this out using a camaro clip on a 50 chevy pickup, 7 inch rims would touch fenders.:welcome: Rick
i assume you have that s -10 stuff just laying around but if your wanting to build a quality street rod with minnamal work and frame fabrication i would use a 1970's monte carlo frame and suspesion you will be very surprised at how close the frame matches your original
I recently used an S10 frame on my car a 1952 Chev. I took out the camaro clip that I bought it with because it was much wider on the front. The S10 frames are cool because you now have various options for wheels and ride height. My intention is to hammer the wheels right into the wells without worrying if they will hit the fenders when going over bumps. I'm not sure if your pontiac has the same front fender dimensions if it is does it does look really cool with the wheels a little in more than a camaro or nova clip. I'm not familiar with monte carlo clips are they the same as nova's etc. If not what is the difference?