Lightning struck twice today! I had bought the battery-powered HO steamer that I just posted about. But I also bought this loco today. The problem is no matter what I did, I could not get the top off, so I finally made a small break in the back. I installed a single AA battery, and it runs great.
Unfortunately, it doesn't fit on any tracks that I have, but for $1, it sure is a nice-looking piece of junk.