I will reply to you, but I HAVE NOT taken the muffler off of mine, just looked at it.......
Seat should have a 10 mm bolt on each side underneath, right where the curve is steep on the drivers seat. Then rear seat is held on by a single 10mm screw in the center of the fender, will be more visible once driver seat is removed, if yours is a 2 piece.
I have looked at taking the muffle off, but have not. If its like most exhausts in general, you end up taking more off that just what you want to work on......
IF it is hard coming off, soak the joint in a solven that will not destroy your chrome overnight, and be generous with the soaking. Put rags behind it to keep overspray of your bike. Next moring, try to gently tap it off with a rubber mallet, preferably in the area under the cosmetic cover. Could try lightly tapping a flathead in the seam, just be careful, this will easily cause a bend.
FWIW, now that I look at it more, I might be prone to remove the whole shebang, clean back to the head. Pipe and all... Might cost a slight amount extra for a gasket, but looks like it would be bewkew (redneck spelling for beaucoup) easier if the muffler is gonna be contrary while coming off.
Im sure the experts who have done it have a better method.
God bless and good luck,
Farmer