You're doing well on the learning curve, Slayer.
(he goes to Eleven, bless him
) was right after all on the no-goop rule for airhead sump and valve cover gaskets: NONE, unless you have a confirmed
warped-surface condition. It only took me nearly a decade to realize this. Sump and valve cover gaskets go on dry, and the torque is very light. It's over-torquing these (esp the sump gasket) that starts leaks. Lots of goop is a very bad idea, and you can count on seeing orange permatex in the pump pickup
Exhaust nuts: i'm surprised nobody suggested slightly tightening
them first, while warm. Often breaks the thread corrosion before you start removing threads on the dry removal cycle.
I use the engine's recently-run heat to start a soak-in cycle of PB, Kroil, Liq Wrench etc. Let it cool, more penetrant. Use the expansion/contraction cooldown cycles to get the penetrator in the threads. Slight tighten to break the corrosion, then more penetrant, then try removal. No go? Propane and more chem applications. Never stuck an exhaust nut yet. This is also the drill for pulling stuck muffler components apart
High-temp copper antiseize is the tits. I have a big tub of spendy Wurth stuff that's rated to 1000F or some such. It goes on liberally to any exhaust item i touch. Even standard parts-store antiseize will be a blessing next time you hafta take stuff apart