Header pipe question

[Rpmalerba]

O.K, this is what I thought. Otherwise I was gonna install and mount both headers tomorrow, then put the engine guards and floor boards on, and the front panels and then install whatever used mufflers I get from eBay next week. Got it, have all the parts, fit and line up, then crank down. Yes? Also do you put the header tail end gasket on and slide it into the muffler? Or the gasket into the muffler and slide the header manifold end in to the gasket?