Maliwagon, welcome. Your wagon is beautiful! I can't really see any license plates in the pics but it looks a lot like Portland. If so, you're covered for emissions equipment. My '79 has a 305 and only has a cat, egr, and charcoal canister. No AIR pump or anything else.
On the transmission front, A 200-4R is practically a bolt-in with the right crossmember. For the T-5, you can get creative and there are several ways to do it. There actually IS a WC version available in the '93 S10 (I have a couple). It bolts to any common GM bellhousing but you'll need to shorten the imput shaft and throwout collar a little. It's not a tough job and doesn't even require transmission disassembly aside from pulling the input shaft out the front. If you don't want to do the input modification, there are spacer plates available online. The spline is 14x1" and there are 10.5" and 11" versions available.
If your carpet is still in decent shape, you could always re-dye it a darker color. Once you have the carpet out of the car, TIde and a scrub brush works wonders for removing stains. Then hit it with a pressure washer. Once it's clean, Rit Dye in a big tub does the trick.