Note- when I first bought these wings, I noted the a mushroom setmark on the lower inbd skin at the aft spar flange, approx centered between the two inbd inspection panels. There is a corresponding ripple in the spar flange that I was able to see with a borescope.

I didn't really see how it would cause any problems, but since this is my first RV and I'm unsure how robust some of the structure might be, I thought I'd check. Vans tech support looked at the pictures and said don't worry about it, so now I've got written guidance from Vans saying it's structurally ok.

Given the location and difficulty in reworking this, I'm going with Van's advice. I hate the idea of sand and fill to cover up mistakes, but I've seen it on plenty of jets, so I'm letting the paint shop fill this with a few grams of filler when that time comes and nobody will ever know except you and me :)