I appreciate all the help, guys, but I have to make clear that I am NOT going to be doing any tire work on this or any other vehicle, EVER (bicycles being a possible exception). Attempts at motorcycle tire work led me to conclude that I have NO business messing with such things, because I have ZERO patience for it. NONE. Things get thrown. Hard. Heavy things.

Having said that, today I reiterated to the counter guy at GCR my concern that there is FOD between the tire and the tube, and that talc might be a good idea. He said he's going to order a new tube, and we'll start the whole idiotic process over again.

If this repair doesn't hold (and I have no reason to believe it will), I am going to pursue having the wheels modified to run tubeless tires. A guy I know in the resto business up in WY has a source for this, and I am very interested. If it checks out, I'll probably pursue this anyway because I no longer have any confidence in the tube/tire system.

I checked out Stockton Wheel, and if their wheels didn't look so disagreeable, I'd go that route. Still might have to.

Thanks for all the help, everyone. The mystery (AFAIK) persists.