It's dimpling time! I dimpled all of the ribs using the squeezer, then dimpled the rear spar. Van's also says to slightly countersink the holes in the rear spar so that they better accept the dimpled skin. This is simply because of the thickness of the material, so it doesn't dimple quite as deep as it should. I used my deburr bit to just take a bit of material out of each hole.
The hole for the pitot tube is just a small pre-punched hole in the spar that has to be upsized. I counted, recounted, and counted again to make sure I was drilling in the right spot. The hole gets drilled to 7/16", through the skin as well as the spar.
The monotony hadn't quite gotten to me yet, so I soldiered on and countersunk all of the holes in the spar for the skin rivets. That was A LOT of countersinking - both top and bottom sides.
