Drilled the fuel tank attach nutplate and wing attach nutplate rivet holes in the web of the spars. Drilled the #30 holes in the spar doublers. Countersunk the nutplate attach rivet holes in the web. Also primed the countersunk holes in the flanges of the spars with Akzo-Nobel primer. This would otherwise be bare, and though there is a rivet covering it I will feel better knowing there is a little more protection for the metal there.