Well, the scooter is back together!
Spent a couple hours filing down the welds on the muffler, namely the restricting factory welds right where the end collar attaches to the head pipe. All sanded smooth now, and installed with the proper exhaust gasket. The only bad thing about the day, besides the rain, was that one of the 2 threaded exhaust studs spun in the head. :bawling: It holds the muffler just fine, but if I ever have to back that acorn nut off...I'll have another project.
Motor started up just fine after I rolled the bike out of the garage. A little smoke from the exhaust, but runs smoothly. Can't tell if the small differences I notices on the short test ride were all in my head, but the throttle response feels smoother and more urgent than before. Less squeaking, too, ha.
Hopefully the rain will be gone by monday and I can take it out for a longer shakedown ride and grab some better pics.
Scrubbed the outside of the motor so it would be easier to spot any possible leaks later on. Safety wired the acorn nuts so I won't lose them again. MLS head gasket seems to be working fine so far, thank God.