Newport77,
It's probably just the needle and seat not shutting off the fuel. You have to rebend the tab on the float to adjust for the right height. On real hot summer days it is good to adjust for a little more pressure on the seat to keep it from leaking and causing the the fuel to over flow.
Here are a couple of ideas.......first you can install a fuel pressure gauge before the carb, see the last photo on the link below. I took that shot while drag racing. WIth the hood open and the sun shining in the gauge went up to 15 pounds or so just from the heat while waiting in line. I had installed a needle and seat that was metal on metal so the ethanol isn't deteriorating the usual rubber tip on the needle, which keeps the fuel from coming in very well. Starts at the line were very crisp all the time even when we had to wait 20 to 40 minutes. They had blown engine clean up, replace lights on the tree, etc...
The second idea is running an electric fan. I leave mine armed after shut down so when heat soak starts the fan automatically kicks on and runs to cool the engine and carb down, thus minimizing heat soak and carb boiling and flooding problems. On 90 degree plus days my engine starts up with a bang and is not affected by the problem.
The third idea, is on the aluminum heat deflecter I run a 1/2" thick gasket above and below it to insulate the carb. The aluminum not only reflects the heat but acts like a heat sink and when the electric fan kicks on it cools down very quickly.
Hope these (3) ideas help you.
Click on the red link below and then click on the picture to blow it up full screen size into slide show mode. Reference the last picture. I moved the fuel pressure gauge to the carb line right off the fuel filter. Then I could see the higher seat pressures the carb was seeing and not just the fuel pump output. All three upgrades work well together to minimize the heat soak effects. We had four Darts back to back in a row in our line and some had a hard time starting after the long waiting times between rounds. Mine always fired immediately. I couldn't get my hand off the key fast enough........