Sand and apply second layer of epoxy with filler to the outside lower cowl exhaust outlet. Mount Skybolt flanges to upper cowl firewall. Tape 10 Skybolt cleco drill bushings to the flanges working from the center flange to the left and right side. Place and level upper cowl. From under the cowl shine a flashlight through each cleco drill bushing hole and mark the light spot seen on the outside of the cowl. Drill #40 and then #30 to align the cowl hole with the hole in the busing. Drill 13 of 17 upper firewall Skybolt flanges.