I went to Home Cheapo, and bought a sanding block with velcro backed paper. I used 50, 80, 120, and 220 to get the seams smoothed out and the rusty spots knocked down. The seams where the different panels come together was the worst, particularly on the bottom. It was so hard to get a good angle on the bottom seam that I finally gave up and painted it anyway. It will probably rust again in the not-to-distant future, but like I said, it was cheap.
The painting took me a week to do it all. I painted the inside first. I started with the bare metal, and rusty spots first. But since it was the most humid week so far this summer, it took forever to dry. It had hardened enough so a firm touch wouldn't leave a fingerprint, but it was still tacky. I got the inside to a point where it looks good from about six feet up, and I taped off the top to be able to spray the outside.
I ended up using one and a half cans of the black epoxy to do the whole outside. I would do one side at a time, and put down just enough paint to leave a splotchy black and white look. Then I would come back the next day and do a little more. The last day was just coming back and hitting the few spots that I had missed and I was good to go.
The temp controller wasn't bad, and I just hard wired it to the freezer, instead of putting in an outlet like I have seen some do. The ground pin on the freezer plug was broken off, so hard wiring it was an easy to fix the grounding. And I put it all in a 6" x 8" project box from Radio Crack.