I made the upper wing root fairings out of .025 inch 2024-T3. I'd previously installed dimpled 6-32 nutplates on the inboard edges of the wing, and I used homemade hole finders to copy the hole onto the fairings. I overdrilled the the fairing holes with a #27 drill bit and dimpled them. After the outboard edge of the fairing (inboard edge of wing) was finished, I drilled #40 holes in the fuselage channel, and used the hole finders to copy the hole onto the inboard edge of the fairing. I then redrilled the channel with a #38 drill bit and tapped the channel to 6-32. I then over drilled the inboard fairing holes with a #27 drill bit. I drilled an additional hole in the forward fairing, dimpled it and placed a nutplate on the upper fairing so that the leading edge of upper fairing would be well secured.