Cut out the lightening holes of the center rib except the rear ones. Had to go back and make 2 more .032 ribs because of a design modification made after my plans that requires doubling the ribs at the wing root. I took pictures but for some reason they did not save. All the center ribs now have all the lightening holes except the rear one. Some questions remain on what shape and location this hole should be due to some design changes that happened after my plans were released.