The interior panels are pretty resilient! I started with compressed air, and got a fair amount of the loose paint off. It seems that where it didn't stick, it didn't stick at all. Where it did, it's one with the panel. I proceeded to using a stainless steel parts cleaning brush, but was afraid I'd scratch the plastic if I went too hard on the pressure. Tape was good, too, but kind of a waste of tape, IMO. I also tried glass beads in my media blaster, with the nozzle held about a foot away from the panel. I wasn't seeing a lot of progress from it, and it left a 'haze' of dust on the panel.
I then tried brake cleaner. It did okay, but seemed to get only the stuff that was already loose up. I progressed to an electrical circuit cleaner, which did nothing, probably because it dried too fast, then on to carburetor cleaner. It contained toluene and acetone, and really did the job, expecially along the edge of the panel, where the paint seemed to stick the best. I think I have most of it off, and since I have the panel already washed in acetone, think I'll have another go at repainting the panel.
Fingers crossed.....