I saw that set in bob's garage. The dryer is pretty well done, he transferred the entire top of an older model on a newer base. He said that the wiring was pretty straightforward
heat welding the two polypropylene skirts together
Tom, thermoforming plastics generally weld fairly well and it's a pretty simple thing to do. Polypropylene is one of the easier plastics to weld too. We have a plastic welding setup here at the machine shop. Years ago we made a number of tanks and fixtures all from Polypro for a local semiconductor manufacturer. Years ago I worked with a local motorcycle shop and we welded broken fairings, most of this was ABS (easy) or Nylon (not so easy).
A plastic welder is basically a concentrated heat gun that looks like a large pencil-style soldering iron. They will use either compressed air or nitrogen or other inert gas which the element heats to as much as 900 deg F. Often times there is a tip that has a plate that helps press the filler material into the weld area.
Joint design is very important for plastic welding. The filler material goes soft (plastic state) but never really flows like when welding metals. It is important to get a close fitting joint. Provided two agitators could be fit together decently they could be welded easily and securely. Dr. Frankenstein the lab is calling!