edelbrock gasket choice - heat insulator worth it

The biggest benefit in that area is to block the heat crossover. If you live in a frozen climate for several months out of the year, I don't recommend it due to carb icing. However, if it rarely gets into the 30's go for it. I do prefer to use a well tuned manual choke when I've got my crossover blocked, and live in a moderate climate zone where I don't have icing issues.

If you have hood clearance, now is the time to put a phenolic spacer or sandwiched aluminum plates and gaskets. If you combine this with an insulated return bleed fuel filter near the carb or a complete return regulator with insulated lines near the engine & exhaust, you will have the complete package for cooler fuel delivery and less chance of vapor lock and it's related issues.