Thanks for the tip. Copper would form and be gas tight. This is an original '64 Dart that appears to have low miles and it was in storage for years, and now runs great except it needs a new clutch and re-seal the trans. Moving the exhaust pipe gives a bit more room, but could work around it...
I have a '64 Dart with 273 2v engine. I'm having difficult time finding exhaust flange gasket for my 273. Parts houses have exhaust flange gaskets for slant 6 and for the HIPO 273, but no listing for the base 273. Think mine is the 2.25 diameter exhaust. The gasket goes between the Y pipe and...