Dwight, back a number of posts you posted photos of the plugs - those plugs are carbon-fouled from the engine running too rich, as others have said. Carb rebuild and adjustment should handle that.
But with regard to the no-start when hot issue, I'm thinking bad coil at this point. I skimmed the 7 pages of posts, and I didn't see that had been replaced. Maybe I missed it. Before throwing another part at the truck, you may be able to diagnose by warming the coil with a heat gun, or alternatively cooling it when in the no-start condition with electronics diagnostic cold-spray. In a pinch, dust-off spray can work, so long as you get a good blast of liquid, not just gas. Or even easier, if you have a known-good coil, do a quick swap when in no-start condition.
