I cut some small squares of 1/8 ply and epoxied them over the wing bolt holes on the top of the wing. I then sanded the edges with a sanding drum on the Dremel. It should be not more than 2 bumps under the Ultracoat, but I felt that the small section of ply at the trailing edge that the instructions call for as inadequate.

Another problem that could be important before you get too far into the fuselage build- Look at the wing block placement carefully. It is misleading in the book. The blocks should be glued back against the former F3 and not 1/2" forward as in one dipiction.