Marked the backing plate for drilling per the plans. Had to adjust the rivet line on the outboard edge for edge distance on the angle bracket.
Match drilled the backing plate to the spar holes, then drilled the rest of the backing plate on the drill press. Cleco'd the backing plate and skin onto the wing, where the plans called for match drilling these from inside the wing. I could not get a drill into the wing to do this, so I marked the streamline hole and the large screw holes as reference points, removed the skin, cleco'd on the backing plate and match drilled on the bench.
Used the step drill to drill a 1/4 inch hole at the aft end of the streamline and a 1/2 inch hole at the forward end. Drilled the perimeter and cut out the remainder with the Dremel. Used Dremel grinders and sanders to shape the edges of the hole, test fitting the streamline tube to keep the hole as small as possible. When the tube fit nicely and the screw holes aligned, I edge finished the hole with files, emory cloth and scotchbrite. Deburred all drilled holes.
