The inboard rib can be modified to include an inspection plate. I put it off until today because I didn't have a fly cutter big enough (5 inch diameter). So I cut the hole on the drill press then cleaned it up. Then I drilled the screw holes to # 19. Next is the nutplate holes to # 41. The rib gets dimpled and the reenforcement ring gets countersunk to the dimples. Next the nutplates went on with flat 3-4 rivets. I had to drill one out but it came out surprisingly easy. The CP drill's controllability is already paying off. The inspection cover goes on with a cork gasket...not feeling good about that area's ability to hold back fuel. There's a lot of holes in that area, and I can't imagine not seeing a leak there eventually. I'll probalby just put sealant on it and sacrifice it if it ever has to come off.
