Well I started, a little vinegar & wire brush. It started coming off, it's gonna take some work!
What's all this alphabet soup AMNPS, AMNS???
I hope I got the right stuff; being cheap I ordered a 'scratch & dent' (looks like new to me) A-MAZE-N-PELLET-SMOKER 5X8, and added 4# apple dust. I got it in like 2 days (FAST!), and it had the dust & a bag of pit masters pellets included (not mentioned in the scratch & dent ad as included; but I now do see it in the regular priced version). So it does appear I can burn both dust & pellets.
Prior to it arriving I did smoke a chuck roast, just a baby 2.5#, took ~6hrs (wrapped in foil after it stalled at 170 for an hour to get it to 190). It was OK, was hoping for better; but I think it was the wood flavor (I used a pre mixed oak, hickory & apple blend) and we don't seem to have a pallet for some of these non-sweet/fruit woods. It was tender; just not fall apart soft. I did get a big smoke going with each load of chips; but it quickly tapered off.