1. Removed middle top skin. 2. Cut 4 "L" angles to the length shown on dwg 6B21 to form stringers. 3. Drew rivet line down each angle. 4. Drilled first rivet holes in stringers on baggage rack bulkhead end. 5. Laid rivet pattern on middle top skin. 6. Punched and drilled with #40 bit. 7. Replaced smiddle top skin on aircraft. 8. Starting with the stbd lower stringer: A. Cleco aft rivet hole. B. Located rivet line through fwd rivet hole in skin. C. Back drilled with #40 bit, holding wooden block against stringer. D. Drilled intermediate holes with #40 bit. 9. Repleated steps A-D for all four stringers. 10. Opened all stringer rivet holes with #30 bit for A4 rivets. 11. Clecoed.
