I spent a couple hours in the morning and again in the afternoon cleaning up the Dansk. I'm at work, waiting for actual work, so it's just a productive way to pass the time. I hadn't taken a picture of the bottom side of the muffler, but it was coated with burnt black paint.
I used some acetone and a scraper on the worst parts, then a nylon wheel and 3M pad on a sander.
It looks pretty much like a normal muffler now. Tomorrow, I'm planning to use a Dremel on some of the smaller spots, then work towards more of a polished finish. There's one weld on a bracket that needs to be repaired. The rest of it is in good shape.