I know that furnace well! It was selling when I was in the business. It was a nice stove. The thermostat setup works well and should last forever. Check out the firebox for any cracks, etc. before you try to fire it up. If you find any, get them welded (or do it yourself if you are a welder). In fact, a good way to test it out is set it outside on concrete and put a short stovepipe on it. Fire it up outside to be sure you don't have any firebox leaks. Then let it cool down and move it inside the workshop. A new coat of hi-temp black paint (you can find it at most wood stove/fireplace shops) will make it look almost new! If you do paint it, the paint will stink when you first fire it up. Open a couple of windows and it will subside shortly. The sheet metal shouldn't be a problem. Remember, don't cut corners on the chimney!!