Not sure what year they debuted, but if that truck has the two ton Chevy 10 bolt 8.75" bolt circle motor wheel pattern, then you can just buy brand new 22.5" steel wheels for it. Pretty sure you can get the smaller 10 hole pattern in 19.5" wheels, too. Accuride used to make a set of the two ton Chevy wheels and they were lighter than the Sanska ones I just bought, but the Accurides are hen's teeth these days, where as the Sanskas can be bought in any quantity desired for $299 apiece online, with free shipping. They're made in Turkey, oddly enough, also DOT stamped; it's my understanding that there was a run of these wheels made in China that were not DOT.
And yes, radial tires make a really big difference, especially if you'd like to exceed 55mph or go around a corner or not have the rig shake itself half to death from the cold flat spots on old bias tires, or follow the grooves in the road. Also, less rolling resistance equals better fuel mileage. Unless you need the exact look for a vintage restoration to roll in a parade, I can't think of a single reason to run bias versus radials on a rig that you actually intend to drive.
