I think the felpro gasket is diff . The copper head gaskets gives away too much compression. They do come off real nice? I dont think you will want to put any sealer on the gasket unless you use a copper one. My 235 leaks with a copper gasket. and my 261 has the felpro with a PVC valve from a 292 and a good breather cap and it has been dry as a bone for 1 years now. Your head gasket black or blue?