-4 Fuel Tank Ribs - HELP!

[WSBuilderHM]

I've fluted all the main and LE wing ribs and tried to begin on the fuel tank ribs. Up to this point the ribs all matched the fluting plans profile and tooling holes fairly closely, but the fuel tank ribs do not. When I align the aft tooling hole, the fwd hole is one diameter off. Also, the aft edge is five degrees out of parallel with the drawing profile. I compared with the LE ribs and they are not parallel to those either. All the fuel tank ribs are like this. Why?

[joeboisselle]

Someone here might have a good explanation for it, but I think this might be a good question for Vans. I had some questionable wing parts also.