[jrmunn]

I don't know if this is the best place, but you might find my experience useful. My 1964 GMC 1500 came with 15 inch two-piece wheels that required use of tubes. I understand that you want to keep your truck original, and I held out with the 15 inch wheels and bias ply tires for many years, but I finally gave in when the local tire dealer became less inclined to work on my wheels and most pickup trucks were running on radials. My switch was to LT235/85R16 M+S load range D Radials, which required getting new one-piece wheels. I have never regretted it. The bias ply tires would track in grooves and occasionally would "jump" to the left or right without really changing direction. This was not from pulling because of poor alignment. The ride was stiff, and the tires would develop flat spots (especially when cold) that took several minutes to roll out. All of this went away with the switch to radials. Handling and ride greatly improved, I am getting more miles from the tires, there is much more to choose from, and the new tires are a little taller which slightly reduces engine rpm while providing a few more mph on the open road.

However, there was an unanticipated problem. I measured to be sure a new spare tire would not be too wide to fit in the space under the bed, but forgot to check on depth. As usual, what I didn't check turned out not fitting. It only took a longer piece of threaded rod to accommodate the bigger tire, but this is something to keep in mind.

Good luck with your choice of wheels and tires. Personally, I like the radials.

JRMunn