[FUNFER2]

Yes, I just use silicone, the "Permatex RTV high temp silicone" (red). I assume that your headers & collector are the four into one ? I follow the outside edge & around each tube to totally seal the sidepipe flange/collector. I do the same thing with the sprint car engine including mounting the headers to the head, all without gaskets. Apply and let it "skin over" then bolt the two surfaces together. I wait apx. 24 hrs to start the engine. I never get a leak. I believe you can get a cork sheet at NAPA stores, cut to size & use the silicone.