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Probably still the same problem. The heat soaks into the carb and boils the fuel out of the bowl. An aftermarket carb spacer on mine fixed the problem.
Another thought is fuel pressure. Too much fuel pressure and heat expansion in the lines after shut down can cause flooding by overcoming the needle/seat. Ethanol in the fuel doesn't help either. Vapor locks, boil off and evaporates quicker.
something else to think of is fuel dripping into the engine after shut off from the carb. this might flood the engine and what seams like a cool down time might just be the fuel evaporating
Get it so the condition occurs and shut the engine off. Let it sit for the 20 minutes, remove the air cleaner and verify the choke is fully open. Looking down through the air horn actuate the throttle and verify fuel is discharged from the accelerator pump nozzles. How is your distributor advance connected, ported or manifold vacuum? What is the base timing set at?