Before installing the stiffeners, I refabricate the gussets I had an edge distance problem with. Here is one of them clecoed in position.



Then I drilled into position the four lower skin stiffeners. Help is needed for the two outboard ones as it's impossible to clamp them into position. Sabine gave a hand for this.



The inner stiffeners the get drilled to the support on the main bulkhead



and on the angle on the firewall. The angle drill comes in handy for this holes.