Hey guys, wow, thanks for all the responses!
I re-read the "lugnutz" link posted above and saw that the <'88 S10 T5's have the mechanical speedo, and the camaro T5's were mechanical up to '93...that is probably what I was remembering from years ago when I was researching this before we did the engine rebuild...will certainly sus out any trans I find to make sure it is the right tailpiece.
Mr. John M - thanks for chiming in and for keeping such a great resource alive! As I mentioned earlier, I looked for a center section to put into my HO52 for many years, with no luck. I'm not exactly in the best location to find stuff like that unfortunately. Also, the SM420 is rather loud until you get into 4th gear, and I'd like to have something quieter if possible...but I would not be opposed to trying the gear swap if I could find a good donor, or just swap the whole axle in there...I called around to all the junkyards within a several hour radius from me, several times over the years, with no luck. I have come across some options on facebook marketplace, but nothing has panned out.
I am definitely concerned about putting a 5 speed designed for the iron duke behind the 235...but they also came behind the 4.3 V6 and the 350, so I know they can be stout. I also have a line on a '92 camaro T5, but the guy wants a grand for it which I think is steep.
As for the in-cab tank...maybe you can't smell the gas because the cigar smoke drowns it out?

just a thought, hehe...
The $2k price tag was just suspension / steering replacement parts, as I priced them out online. No trans, no labor.
Honestly I'm surprised that so many people get hung up on the term "drivability"...maybe it's a generational thing? (I'm in my early 40's, so a gen X-er.) I have owned and driven lots of trucks, full size, small size, 2wd, 4x4...some of them I would say had good drivability, some not so much. I think I mentioned this before, but what I'm looking for is a ride that won't rattle your teeth out or bounce you off the seat driving around town, and a comfortable gear spread so that in-town driving doesn't feel like a tractor pull, and 55 mph isn't screaming the engine. Pretty simple.
I had an OBS F150 regular cab that fit that description, as well as a few Toyotas and S10's. That is the ballpark I'm going for. I've only ridden in a few classic trucks besides Spud, and none of them had a stock front end suspension.
We're heading out of town on vacation for a few weeks, and when I return I will be looking to pick this back up and make some progress. Gotta clear a spot in my shop - too many boats in there right now!
Cheers all and happy holidays!