I cut a section out of the lower cowling to create space between the cowling and the engine exhaust. I used the same modeling clay method used previously to make a form for a fiberglass layup and made a blister on the bottom of the cowl. I ended up with about a one inch space between the exhaust and the cowl. That should be plenty of space to protect the cowl from the heat from the exhaust. I attached the new fiberglass blister with fiberglass resin adhesive and rivets.
