Leak tested fuel tank. We sealed filler hole with a baloon, capped off the bottom sump fitting, put screen and hose fitting on and attached fule hose. Pressured tank by blowing into fuel line hose and sumursed in water. No Leaks! Cut and layed out U-rib channels (7V11-4K) for length and rivets, drilled & clecoed. Drilled out 4-rivets on spar at station 300, (7V3-2SP) to install U-rib channel using those same holes.
