I'm at home on dial-up (we don't even have cable available out here in East Bugnut) so these will be in short bursts.

I used a straight spar to describe the line down the top of the frames for the turtledeck.

By laying pins on the top of the frames and pushing them through the side sheets, then laying tha spar on that I was able to find the straight line (this is a boatbuilding trick of sorts).

I scribed the line with a ball-point pen (easier to draw with and see on balsa) and then llifted the spar 1/16" to allow for sanding to the proper angle. You can see the "trapped" pin that shows I'm pretty close to done at the initial cut. A spirit level and a razor plane, then 150 grit on a sanding block and it is flush to the frames in 15 minutes.