Survey '64-'66 Barracudas

I actually invert the fill nozzle so that the hose from the pump is facing up. But I also practice not filling at full speed for the last half of tank and carry a rag or grab paper towels on the island to quickly mop up spills with. Modern gas pumps and car fuel systems are designed for higher fill rates than our older car systems can often deal with. Have you checked your vent line to make sure it's clear? In areas with strict vapor control laws, where the pump boot has to be pressed/sealed against the fuel neck, a plugged vent line can create excess back pressure like you describe. I suggest the vent line because when I overfill my car it just runs out but it does not spew or blow out as if there is air pressure pushing it as you described.