I began construction of the alternate air door for the fuel injection air induction system, which mounts to the left side of the FAB snorkel. I selected a spot on the snorkel's side and drilled the 3.5" hole for the door base plate, then match-drilled the rivet and screw holes.
I then applied epoxy/micro balloon to fill the gaps between the base plate and the snorkel (makes an air-tight and durable seal). I used Turtle Wax on the clecos to ensure they'll release after the epoxy has cured (they did).
Image 3 is from 9 September after the epoxy cured. I riveted the platenut to the bottom of the base plate, then pop-riveted the base plate to the snorkel.
Air Door hole cut into snorkel, rivet holes match-drilled
