On page 14-02, step three, it says to dimple the lower flanges of all the wing ribs. I've been reading ahead to see where the plans say to finish dimpling the upper flanges, but that doesn't come until page 16-02. How can that be? The ribs get riveted to the spar back on page 14-07. It would be so much easier to dimple the upper flange of the ribs using the DRDT-2, but of course that is impossible if the ribs are riveted to the spar. Surely this is a mistake?