The replacement parts arrived, so I replaced the mangled C-759 inside skirt on the passenger side. It's visible just above the lower canopy frame tube in this photo:
Then I drilled #30 holes through the pilot holes I'd already drilled in the outer canopy skirts, into the plexiglass, and out through the inside skirts. I used a plexiglass drill bit to go through all three layers, and it worked okay. The plexiglass bits seem to be able to go through thin aluminum without too much trouble.
After drilling, I removed the skirts and deburred all the holes. No reason to get a drill chip wedged in there and start a crack.
Then I made a new pair of C-791 canopy skirt braces. This time, I ignored the lightening hole spacing given in the plans. Instead, I located the holes and slots so they'd be sure to miss the rivets that attach the braces to the C-660 skirts. I also moved the forward-most lightening hole back an inch or two from the plans location, for reasons that will be made clear below.
The adjusted spacing gave me 9 lightening holes per part instead of the 10 called for by the plans, but whatever.
Then I crawled into the fuselage, slid the canopy shut, and drilled and clecoed the skirt braces to the slider frame. (This photo is actually from later on, but you get the idea) Then I had to remove the clecoes so I could open the canopy and get out.
Al came by to help with the next step, since it requires two people and Mary was at work. I sat inside the fuselage and held the bottoms of the skirt braces flush against the skirt with a wood block, while he pushed the skirts in to be flush with the fuselage sides and drilled the rivet holes from the outside. The goal here is to get the skirt braces to pull in on the side skirts so they sit flush with the fuselage sides at rest, and resist bowing out in flight due to the low pressure air going by the sides of the canopy.
Here's a view of the finished product, looking up at one of the side skirts from below, with the canopy shut. Except for at the yet-to-be-finished aft end, the fit is excellent. You can just barely get a piece of paper in between the fuselage and canopy skirt. Once the UHMW anti-scuffing tape is applied under the skirts, there should be a pretty good airseal here.
This photo explains why I moved the forward lightening holes in the skirt braces. It let me cut these little notches that prevent the nut holding the slider rollers to the frame from bending the skirt brace, as I've seen happen on other RV's.
I also had to do some trimming at the aft end to get the skirt braces to clear the anchor pin thingies.
