Today, I began by countersinking the holes for the rivets that attach the small tip rib. The rib is now ready to install permanently, but I'll wait until all the other wingtip work is accomplished before riveting it on.
Next, I countersunk all the attach holes in the R wingtip for #6 screws. (One hole in the top and another in the bottom of the wingtip were countersunk to #8 instead. These two positions, just forward of the spar, will accommodate small attach-plates for GoPro video cameras. When the camera(s) are not installed, the larger screw will hardly be noticed.) I installed two #8 floating nutplates at these locations.
All the other positions are #6 nutplates, and I decided to use ClickBond floating nutplates, which are bonded into the wingtip instead of riveted. There was a bit of head-scratching as I figured out how to use the mix/applicator gun, since the ClickBond kit instructions contained references to a completely different method of applying the adhesive. I eventually got everything figured out, and found the installation process to be kind of fun. Basically, you apply adhesive to the underside of each nutplate, stick the wide end of the rubber stem through the hole, pull the nutplate down into position, then pull the stem so it stretches about an inch, and release. This sets the nutplate firmly into position and squeezes out a bead of adhesive. The spec sheet says the adhesive will be 90% cured in 8 hours, and 100% cured in 24 hours, so I think it will be fine to handle tomorrow morning. This stuff is used by Boeing, Northrop Grumman, and Airbus Industries, so it should be good for a lowly RV-8. :-)