SCE now makes a round port header gasket like the Remflex. 1/8" thick graphite composite. Maybe they will fir better.
https://www.summitracing.com/parts/s...1/make/pontiac
Flatout makes a rubber coated copper gasket for us.
https://www.summitracing.com/parts/f...c/make/pontiac
And we might be better off with a tube of red RTV.