Removed bolts and rivets on the rear spar plates. They removed to the inside.
Removed center spar byt removing both front and one rear upright support. They all will be removed and reattached later alnog with the support plate on the outside of the skin. We didn't have to remove the entire seat pan, just along the sides, front and center. The rear line of rivets that go to the main gear channel were left in place.