Getting close to riveting my wing ribs to the spars, and I noticed some pre-drilled holes in the main spar near the root that look like they will house nutplates one day. I looked ahead in the plans and drawings, but so far did not find any reference to what these are for or when they go in. Seems like it might be easier to attach nutplates now, rather than after the wing walk ribs are riveted in, making it a tight fit. Or should I stop trying to think ahead so much? What are these for, and when are they supposed to go in?