Machine countersink the spanwise rows of holes in the T-701 tank skin (not the baffle) that attach the skin to the T-702 baffle. Have the baffle in place so that the pilot has a good hole to guide the countersink. This makes it easier to slide the baffle into position on final assembly. Drill the spar attachment screw holes and the W-423 screw holes to final size using a #19 drill.
I finished the match drilling the rear baffle to skins. Countersink the skins for baffle. Drilled mounting holes to final size #19
