I had an imperial in here monday for similiar problem, edelbrock starting when hot. I added a fuel pressure gage to the fuel line at the carb and we let the engine idle, i took temp readings with a gun and the engine became stable at 160deg, (heads, carb base and radiator top) and fuel pressure was 5lbish. When we shut the car off i watched fuel pressure (it is trapped at 5lbs between the satisfied float and fuel pump check valve) after a brief time it dropped to 4lbs, later to 3 1/2lbs and so forth. I was watching the effect of the fuel boiling in the bowl and forcing fuel out into the carb, the float would drop and allow more fuel into the bowl and the cycle would repeat itself until there wasn't any fuel left in the line and the fuel in the bowl evaporate.
I took the carb off and saw fuel in the wells of the rear 'gate', the only way fuel can get there is from being forced out of the boosters. I checked the carb for other 'oddities' and ressembled everything and used a mr gasket #98 isloator, a sandwich affair of alternating layers of aluminum and gaskets. We started the engine and got it back to the 160 degrees, the carb was now 30 degrees cooler and when we shut the engine off the fuel pressure stayed constant at 5 lbs.
I wish i had both a phenolic and a wooden spacer to compare but i didn't.