210*, even 220* is not overheating, nor is it really anymore than "just a little warm". For an engine that runs at 190-200*, temps will commonly exceed 220* on heavy load situations like long hill pulls, traffic with the a/c on, etc. I would not worry as long as the temp remains under 235* which I consider HOT, although properly mixed and under pressure the coolant is far from boiling.
It sounds like you are suffering from a combination of heat soak, fuel percolation and most likely a weak starter. It's reasonable to assume you have headers and adding a heat shield to the starter or replacing it with a PMGR starter will give you the juice to overcome the "kick back". A phenolic spacer under the carb and even a heat shield can help the percolation. If you live in a warm climate you can also plug the exhaust crossover in the manifold to help. Last, but not least, the "dieseling" or engine run-on after shutting the key off is typically aided by an idle speed that is too high combined with too lean a fuel mixture
It sounds like you are suffering from a combination of heat soak, fuel percolation and most likely a weak starter. It's reasonable to assume you have headers and adding a heat shield to the starter or replacing it with a PMGR starter will give you the juice to overcome the "kick back". A phenolic spacer under the carb and even a heat shield can help the percolation. If you live in a warm climate you can also plug the exhaust crossover in the manifold to help. Last, but not least, the "dieseling" or engine run-on after shutting the key off is typically aided by an idle speed that is too high combined with too lean a fuel mixture