I have an issue with a surge at idle after driving for awhile. I suspect since this is a stone stock 69 440 car that the carb is getting way too hot for the modern gas. If I put on a thicker gasket, will the choke pull off need a likewise raise? Will that still work when raised out of the well?

There used to be a 3/8 tall spacer that came in avs rebuild kits that might do enough for me. I used one on my last car with an aluminum intake and it worked great. I tired it back to back with a thin paper gasket and the slight hot start lag went away and the engine fired right off.