Thunderbucket and Firebird, I was thinking the same thing as the two of you but I went back and read it again. He says it is turning over easily. That puzzles me. Although it might still be the starter,It might possibly be that his headers or exhaust are running too close to the starter,cooking it. If thats the case if he puts a new starter on ,he may need to rerun the exhaust or at least put a starter heat shield on it.
Then again ,Mike might be right on.
Thomas, are you using any spacer between the intake and carb?If not You might consider that, plus make sure the fuel line itself is not getting too hot.Just a couple more things to consider. Good Luck!