If you feel the stalling in heat related I would buy some of the 1/2 inch ID pipe insulation, and cover the lines to see if the stalling is affected:
Ljnk:
https://www.homedepot.com/p/Everbilt...5812/204760811
In 1977-79 Pontiac had factory fuel lines from the fuel pump to the carb that were foam insulated for preventing vapor lock.
My parents had a ford motorhome that was so sensitive to ambient air temps, the only time they could travel was after sundown. I insulated the whole fuel system, and built an air intake under the front bumper to duct cool air to the carb. I ran the fuel lines inside the duct to cool the fuel as well as the ducts blew cool air directly onto the front of the fuel bowl.
This solved the vapor lock as well as increased the mileage about 1 1/2 MPG. They lived in Phoenix, so it was tested under the absolute worst possible conditions. No further problems after revamping the fuel system..........
