I wasn't feeling well this morning so I didn't get started working until mid afternoon. The plans call for marking the upper rib to tube hole location with a long #40 drill bit and finishing it on a drill press. It was much easier to drill through the steel on the drill press than by hand. It helps to have a V-block to keep everything steady. Once the initial holes are drilled, you open them up to #27 for machine screws and lock nuts.
Everything was reassembled and set up for match drilling the remaining holes in the skin to tube with a #40, then final sizing to #30.
One problem I see is deburring the hole edge inside the tube. I don't really have the double sided deburring tool, so I may have to pause building the ailerons until I can find one.
UPDATE: Just ordered a couple of deburring blades from McMaster-Carr. They should arrive Tuesday.
Plans call for long screws to attach the rib and tube. I could've used the next shorter length.
Nose assembly ready to match drill skin to tube holes