Question about Edelbrock RPM Airgap - thermostat housing leak

I always hit the mating surface of the housing with sandpaper flat on a workbench top, then use a paper gasket and "permatex indian head" gasket shellac. I had a chromey o ringed T stat housing on a 440 years ago and the ****** leaked no matter what i did.. dear ole dad introduced me to indian head. We sanded the housing flat, used a new paper gasket and the indian head shellac on both sides. Torquing it down right away. No leaks. Years later i always keep a bottle of indian head in with my auto chemicals. This stuffs great for differential covers too, and unlike silicone it can be painted over.