The inspection plate attach holes were drilled and countersunk today. Only 24 nutplates, so ONLY 72 holes this time. :) Here's the a pic of a spot with both attach points. FYI, the hole sizes are specified for these plates (both #6 and #8) on drawing 12... For reference, the #8 screw gets a #19 hole, and the #6 screw gets a #27 hole. The Avery kit has all these drill sizes and also has a #20 countersink (works just fine in the #19 hole) and a #27 countersink. Instead of using Van's recommendation of using a nutplate for a countersink guide, it's easier (and better?) to use a piece of scrap and the correct size countersinks.
Here's the back of the tank attach holes. The back needs to be deburred, so I did all 432 holes this evening... No problem up front, as the countersink is like a super deep deburring job. :)
Here's all my scrap made into guides. The big piece up top is drilled and dimpled to the correct sizes (written by the correct holes). The other pieces are for (from top to bottom) the individual tank attach holes, the inboard (angled nutplate) holes, and the inspection plate holes.
