Tonight's session started with deburring all of the holes in the J-channel stiffeners that I had drilled last night. I also deburred a couple of the edges, and then labelled these parts and set them aside for now.
Next was to prepare to install all of the nutplates on the right wing spar. First all of the rivet holes for the nutplates had to be countersunk so that a flush rivet could later be installed. My countersinking drill stop cage made preparing all of those holes easy and consistent. I also treated all of the exposed surfaces from the countersinking with an Alodine pen to reduce future corrosion. Then I located the appropriate nutplates and temporarily cleco them in place, since there were several different part numbers needed for all of the spots.
What's next? Tomorrow will be time to start squeezing the rivets for all of these nutplates and countersinking their screwholes.