Brief Description: Section 13-3, Completed steps 1 to 4
11/17/2008 ….. Section 13-3 ...Completed steps 1 to 4 on section 13-3. Match drilled all remaining 3/32 inch holes in the flanges of the W-Spar-Assy L and R. Then machine counter sunk appropriate holes that are used as nut plate attachments. The micro-counter sink was set to just fit (flush setting) the AN426AD3-4 rivets factory head. I then riveted all the necessary fuel tank skin attachment nut-plates to the gold spar assembly. This occurred without complication. Time about 2 hours.