Can anybody solve this hot start issue? I'm out of ideas!

Modern fuels boil over easy so with these old cars hot start problems are common. When hot, if you shut it down, then start it back up immediately it should fire right up without having to push the gas pedal. You did not say how long you leave the car off when hot and that is a factor; the longer it sits the more the fuel boils over. You are in the south I would block the exhaust heat cross over in the intake manifold so that it runs cooler. Then the carb won't get as hot and less boil over.