(1) Clecoed fuel tank to spar. (2) Drilled forward side attach holes for innermost z-bracket, and then clecoed tank to this bracket. To minimize angle-off while drilling, used the 12" long #30 bit attached to the right-angle drill tool. (3) Match drilled tank skin to W-423 joint plate and then drilled out to #19 per drawing. (4) Removed wing leading edge to get access to outboard z-bracket. (5) Drilled outboard z-bracket using same drill set-up as above. Clecoed tank to bracket. (6) Match drilled all skin to rib holes on tank, and most skin to baffle holes. Did not do the top side inboard holes as they were dangerously close to the spar reinforcement bars. (7) Removed tank skin/rib assemble leaving baffle, inboard and outboard ribs attached to spar. This allowed access to drill forward faces of remaining z-brackets.
