My biggest problem was finding the service manual for the WTA3500. I finally found it at APPLIANCEJUNK.COM, which is a sister website to APPLICANCEPARTS.COM. This was a life saver and showed me how to properly disassemble the side panels and remove the control panel. Replacing the drum belt is a bit complicated because the front of the machine has to be removed to slip the new belt over the drum. There is a good video on YouTube that shows the steps for this.