[2blu442]

I think you'll have a hard time getting a Ch*vy 12 bolt for your Olds rear, they're getting really hard to find. An option to consider would be the newer corporate 8.5 10 bolts. They started using them in mid-year 1971 through 1972 Cutlass. I've been told the guts from the corporate 8.5 interchange through 1988 1/2 pickups and vans. Lots of parts available for the 8.5 and much cheaper than the 8.75 12 bolts. Many years ago Supercarsunlimited in Portland Oregon showed me a twisted off axle from his quarter mile car. It was an 8.5 corporate 10 bolt posi. So the torque of the engine twisted off the axle but the gears handled the torque just fine. Something to consider.
John