Fellow S-19 builders Don and Sharon Hall, who live on a small island in Puget Sound, came over with the proper reamer and helped me ream the wing to center spar attachment bolt holes. We first used a undersized drill to open up the spar hole diameters so the pins, that were sanded to the center spar diameters, would fit through both holes. Then pined the spars in place and reamed through using an electric drill at very slow speed. Seemed to work well. Then we bent the aft fuselage side skins. Thanks a bunch Don and Sharon!