Using a flexible straight edge mark position of grooves on inboard nose rib. Use line for edge of nose skin on rear top skin as a guide. This will match up with Spar edge of nose skin when marking. Using this as a guide mark position of rivets to misss grooves and retain 40 pitch for A4 rivets. Clamp guide to nose skin at rib line and transfer marks to skin.
Repeat for each rib. Clean staight edge before each marking.
