Mike, I think your referring to the wood stiffener attached to the last full rib outboard of the aileron. The factory drawing I have shows a 3/8" thick by 14' long pine or spruce part. It sits inside the rib flange and is supposed to brace the rib from pulling in between the spar and trailing edge. It attaches with about 4 small screws. Mine were solid wood and very light at that. I made my replacements out of 1/4" plywood with lightening holes. I think I saw that somewhere over the years and I think it worked much better.
As to other braces between the last 2 ribs, I've seen other ways to do it but I'm not sure how effective they are. I've seen pictures of an aluminum tube, somewhat like the diagonal brace that attaches to the front spar, and I've seen a solid wire screwed to the trailing edge and about 1' up on the last full rib. Good for tension but not good for compression in my mind.
PS, thats the old tip bow, I made new ones. Jim
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. These wings have been a real headache for me. I've covered a couple of fuselages and control surfaces but this is my first set of wings to do completely with new spars, ribs, etc. It ain't brain surgery but certainly taxes the brain 
for a few minutes). Anyway, I looked at the three Champs on the field and two (including mine) have the wire stitich or Martin clip (??) and the other appears to have nothing as far as I can see. 
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