Early on when I used a 4 hole guide template to drill #40 pilot holes in the rear of most of the ribs where they attach to the rear spar. Once mounted, I match drilled #30 through those holes into the rear spar. I did not notice that on the outermost rib, the rear spar doubler (underneath) already had 4 pre-drilled holes which I should lhave used to drill the rear spar and rib all at the same time up through those holes from the bottom. The 4 pilot holes on the outermost rib were not going to match up exactly with the existing pilot holes in the doubler. An email to vans with the appropriate pictures resulted in Vans telling me to just use the existing pilot holes in the doubler, drill up through the rear spar and rib, then add an angle doubler to the inside of the rib that would result in proper strength for the joint to the rear spar. So I did and it all worked out perfectly. The rear spar has only 4 holes, the reinforcing angle has only 4 holes and the mismatched rib flange actually has 5 holes (3 of the 4 original holes matched up ok.) Of course, all those holess had to be countersunk for flush rivets to make space for the aileron mounting bracket which would cover these later. Work continues riveting and bolting up the ribs. Must remember to cut off excess spar flanges outboard of the outer ribs so it doesn't interfere wihen installing the wing tips.
