Just finished working on the wing root fairings. The top fairing is pre-punched and matches the holes on the wing skin. The only possible downside I see to putting nut-plates on top while building the wings, is the time to run screws in to hold the fairing for fitting to the fuselage. I suppose you could cleco through the nutplate, but that may be a little too loose.
On the bottom, the fuselage skin overlaps the wing covering the pre-puched attach holes in the wing skin. (I have the older non match hole fuse, so these holes may be matched on the newer fuse). So you either have to figure out how to back drill through wing skin, or I used a hole finder to pick up the holes. Either way, it would be difficult to do with the nut-plates installed.
N311CR RV-8 - Phase 1