I'm with Dick on the Monza 7.5" housing and swap in the insides from the S10. You have to get the pinion tuned down to match the monza bearings. I think Jim does this at JDrace.com. He's a fellow H-buddy. You'll need the Monza axle housing, Panard bar, and torque arm. Is the trans still in it? Is it stick?
It looks like you've got your work cut out for you. I noticed another Vega door in one of the pix. How many are there?
The fronts are a bit less complicated… sort of. The parts that swap are the spindles and brakes. You should grab that master cylinder while you are at it. OH you can swap in the rear drums too. No need for fabrication for the rear since you have the later chassis you'll have the panard bar mount. SO it's just the irritation of setting up a rear diff. The front you can use the Monza ball joints and get Bob Gumm's adaptors for the spindles or fabricate new mounts for the S10 ball joints. That's a little more complicated. There is a bunch of discussion on this topic in the "Best of"
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