Here is what Caleb told me. I have the same problem with 2 flutes in the tip ribs. I will just flatten it at the holes and if necessary add a little flute next to it.
We caught that issue a couple weeks ago. There are a couple things you can do to correct it. Use the holes predrilled in the skin. I would suggest that you add an L Angle as a doubler. It doesn't have to be very long, just enough to pick up the last hole and the one next to it. Then, depending on which end, rivet the L angle to the web as well as the flange and it will take care of it.
One hole on each end of the H.T. isn't going to hurt anything but that is the best way to correct it. Sorry to the error in the parts.
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