Starter? Coil? Bad ground?

Just recently the car has been having starting problems. It is a 318 with headers, with electronic ignition, Mopar Orange box, stock coil, and a standard size Mopar starter.

The car will start fine on a cold start, and I can drive it anywhere. As soon as I shut it off, and it is warm, it will not start again until I let it sit and cool down. When I turn the key, it makes a clicking sound, like a bad ground. So, I checked all my ground connections (except for the strap between the back of the engine, and the firewall?). They all were clean. So, I am wondering if perhaps the headers got the starter too hot, and now that is what is causing it to not start? And then when it cools down, it starts again? Or does this sound like a bad coil? I read somewhere that when a coil gets too hot, it will do the same thing, but when it cools down, it will start again. Oh, and I already tried changing the ballast resisitor, and it didn't change a thing.