I finished drilling all of the holes in the center spars for the WAFs. After they were all drilled, I removed everything from the spars and varnished the plywood sides. After everything dried, I attached and torqued the landing gear brackets and WAFs. At first I was scared about drilling through the spars. After I figured it out and got comfortable, it was a piece of cake. I even let my daughter drill the last five holes for the rear WAFs.