I fit the skin panel that is over the fuel tank bay. I drilled and clecoed the top side first. I used the MDF center rib forms for support where the fuel tank will go. Once the top was drilled and clecoed I marked the bottom side then removed and predrilled the skin. I put it back on and drilled and clecoed it to the ribs. Then I marked the edges for trimming and removed the panel again and trimmed and deburred all but the rear top edge. I also laid out the skin stiffener locations and predrilled the panel.
