[Formulajones]

If the starter has worn bushings that allows the armature to drag on the winding shoes it will cause a hot start issue, as heat seems to multiply the issue, but will still work find when cold. Sometimes the reman starters today aren't much better or don't seem to last as long.

I usually rebuild them myself with a good quality kit and feel it's a better result than some of the reman stuff out there now.

I run a stock starter on my Pontiac that I rebuilt 20 years ago, and have had both headers and RA manifolds on the car with no heat shielding on anything at all.....drive the car all the time and never an issue, even with initial timing jacked up.

You've done everything else but the starter.....I'm betting it's worn inside and pulling too many amps.