These three views are just to show my method of clamping the wint down and use the benck tipo and the rear spar as the jig I used 1x2 pine board, dry wall screws to clamp the leveling shims in place while I fooled aroung fitting the skins. I think I have a fore-aft stop block too. maybe in the last set of pictures. The idea is to have the spar ribs and skins not move out of aquare and level while wokring on it, and still not mar thing up.
The bench top is sacrifical and will be replaced when the plane flies!