I don't have heat related fuel problems with my 72 Imperial in Texas. The car was 100% stock with the exception of an AVS. I put a 1/4" rubber spacer under the carb. The heat riser and crossover are still in place.
If I let the car sit for several days in the summer I will need to run the electric pump for a moment to refill the bowls. Other than that, it fires right up.
I use one of these cheesy little pumps:
My car is from California and was not equipped with a mechanical pump due to smog pump interference.