A while ago I realized that I should have put a doubler on the inside of the skin where the COM 1 antenna mounted. I removed the nutplates, fabricated a doubler, and alodined it, using an Alodine 1132 pen (Alodine is a type of passive conversion coating to prevent corrosion on aluminum). Today Terry helped me dimple the holes on the skin and rivet the doubler in place.

I also laid up the fibreglas for the plenum chamber transition on the left side of the cowling. I also studied the 12" registration marks, and figured out exactly where they need to go on the rear fuselage, so that they do not end up on top of one of the rear fuselage static ports. And, Terry did a bunch of work on the upholstery for the fabric covered cockpit side panels.