PLeavitt,
Sorry, I lost track of this thread, due to my IAT crisis. Yes, four 10mm bolts hold the lower cushion in. I've taken the seat out about three times, but I only took the cover off the cushion once, and I don't remember being able to access the wire to the heater, because the heater is sewn in to the cover... . I'll take it out today and get an answer by tomorrow and hopefully a fixed seat!