Did most of the alternate air installation:
1. Located and match-drilled the 5 rivet holes and one screw hole for the alternate air port into the snorkel.
2. Removed the port. Deburred the holes. Dimpled the 5 rivet holes. Enlarged the screw hole to #8 size. Enlarged the screw hole in the snorkel to 1/4" so the nuplate fit inside of it.
3. Drilled out the nutplate holes in the ring. Deburred and dimpled them. Riveted the nutplate to the ring.
4. Countersunk the five rivet holes in the snorkel. Drilled two clearance holes for the nutplate rivets in the snorkel.
5. Rounded off the edge of the ring, making it a circle instead of a 13-sided tridecagon.
6. Sanded off the primer around the opening in the snorkel. Cleaned the area with acetone.
7. Mixed up some thick flox mixture and added some cabosil so it wouldn't sag. Spread a bead of it along the backside of the ring, then clecoed the ring in place on the snorkel. Added a fillet of flox mixture around the perimeter of the ring, building it up so everything can be sanded flush tomorrow evening.
8. As the resin began to set, I took two of the clecoes out and pulled two of the five blind rivets.
9. Prepped the rest of the hardware that will attach the door and the Bowden cable.