Each flap bracket (3 per wing) gets two attach angles - one that rivets to the rear spar and bracket and one that is primarily riveted to the skin and bracket. For the first angle, it was a simple matter of clamping them in place and match drilling through the holes in the rear spar. Then the same is done drilling through the holes in the bracket.
The second angle ultimately has to be flush with the skin. To accomplish that, I just needed a flat reference from the rear spar flange to the rib flange. Easy enough with a speed square.
Like the other angle, these were also just clamped and drilled to match the holes in the bracket.
The skins fit great except for the middle bracket cutout, which was just a hair too narrow. After I pulled the skins back off I hit it with a file to open it up a bit.
The last thing for the day was riveting the angles in. The inboard angle went fine, but the middle bracket angle was a nightmare for some reason. I think the spar holes and angle holes were slightly off, because every time I put a rivet in I clinched it, probably because they were at a slight angle. I drilled out multiple rivets and had the same problem over and over. I finally emailed Van's to see what they would think of just adding two additional rivets to the spar/angle to make up for the bad rivets. If this is okay, I'd rather go this route, since continuing to drill the rivets out will inevitably cause the holes to enlarge. If Van's doesn't want me to put additional rivets in, I'll have to remake the angle piece and try to get the holes aligned better.
Side note - this rattle can primer doesn't like to be beat around with tools. It's fine when things go well, but for this problem angle, by the time I had tried to buck the rivets a few times, the primer was in rough shape.
