I first checked appliancepartspros online for parts and prices. I also looked at a couple of videos to aid with disassembly. The videos are excellent, job would be very difficult and some guessing without them. Then I proceeded to tear everything down in the order dictated by the video. I bagged and labeled all screws, washers and small parts as I went along. I got to the hub nut that uses a spanner wrench and got stuck; no easy way to remove it. Since I was going to replace the nut and the shaft and tube assembly, I wasn't concerned about damaging it. So I drilled multiple holes in the nut to take it out in pieces. All other parts were disassembled easily, but I did use an impact cordless driver to help with some tight fasteners.
After disassembly, I took inventory of parts and ordered replacements. I erred on the side of caution and replaced the belt, bearing, seal, shaft and tube assembly and various washers and driveline parts...almost everything that moves along the drive mechanism. Assembly was easy...but in part due to careful prep and previously bagging parts, photos and videos. Assembly took less time than disassembly, maybe half as much time. Now it works like new, smooth and quiet. I spent about $160 on parts, better than $400 for repair or $600-800 for a new machine. The only thing I'd do different in a do over is purchase a spanner wrench or a 1-11/16 deep socket to better deal with the hub nut.