Well, made it to Alabama with a full load in the bed, and a $50 camper shell from craigslist (which I cleaned, sealed, and spray painted..). The TOY was able to keep up @ 70MPH speeds (Thanks W50 Tranny !!). Average MPG was in the 22-25. Not bad for a loaded 1600+ miles roadtrip.
Next plans: Remove camper (done, hanging from the garage ceiling), swap differential (got one from a '89), install a console A/C, and maybe, just maybe, a sidedraft carb setup and camshaft mods.

 

Mission accomplished, time to let it go... Truck is up for bids on eBay:

Toyota Other Pickup Longbed | eBay

See how it handles down the highway at 75+ MPH : https://youtu.be/wqmwTfSr1j8