Heat is everywhere under the car. The fuel pump is obviously hot, when the engine is hot, as is the intake & carb.

Then under the car, where the fuel line runs, is the exhaust system.

In the summer, you also have the added heat from the pavement/concrete

Insulating the lines from any heat source, would obviously reduce fuel temps in those lines.

Several ways to keep the carb cooler. There are all sorts of insulating gaskets & spacers you can use under your carb.

You can also block off the heat crossover of the intake manifold.

An alum intake will also transfer slightly less heat to the carb.

Some use a fuel pump with a vapor return line, in order to keep the unneeded fuel circulating thru the pump & back to the tank.

Then, if you trust an electric fuel pump, you can just not use a mechanical pump. That will prevent the fuel from picking up any heat in the mechanical pump.