Completed step 6 – installed top skin and match drilled the holes in the F=1210C angle. Checked to be sure that the angle was not causing any distortion in the top skin. None was found. Reinstalled the F-1278 top skin and clecoed the F-1208, F-1209 and F-1210 frames and the also the F-1279 R&L upper skins. Completed step 7 – riveted F-12106 forward skin rib to the F-1278 top skin. Had one LP4-3 rivet near the rear of the rib that was not sitting flat. Decided to drill it out and reworked with new rivet using the wedge tool to insure it was sitting flat. Completed step 8 page 10-11, clecoed then riveted the F-1283C stiffener per Figure 2. Completed step 9 – deburred and primed F-00009 L&R ADAHRS brackets then riveted them in place per Figure 2 detail A-A
