BTW, as suggested to me in another thread, you may find it easier to install the new gasket by using a thin coat of Permatex Ultra Copper RTV sealant on the outside before slipping it into place in the female side of the joint. Then put another thin layer on the inside, and slip (perhaps forcefully) the male portion (from the header) into place. It makes the process easier, avoids cracking the new seal, and provides some extra sealant capability. A rubber mallet may be handy - it helped in my case.
Once all in place, tighten the bejabbers out of everything and go to bed. By tomorrow, everything will have set up and you're ready to ride.