Car hard to start when HOT

It's Summer, and my 1970 Dodge Dart with 198 slant six has a difficult time restarting AFTER I've driven the car not too long. The Temperature gauge is accurate and it goes through the roof after only a few miles.

My concern is that the car will turn over and crank, but it won't light and actually vroom. I was told that because the car runs HOT the choke stove attached to the carburetor acts differently and holds the choke open.

I just ordered a whole new cooling system: Thermostat, Water Pump, Heater hoses, and all the gaskets to go with them.

I plan to drain the coolant, remove the ORIGINAL radiator, bring it to a radiator shop to put it in this cleaning "bath", and remove and replace the ORIGINAL thermostat, ORIGINAL water pump, and hoses.

The car starts fine if I leave it for a few hours or overnight to cool, but if you're like me who uses the car as a daily driver during the summer, Starting and restarting is a must.

Thanks!