Joe, AC 43.13-1B applies to repairs made to certified aircraft. You are working on an experimental aircraft, aren't you?
You obviously have conflicting data, and reason will be the first tool in resolving the problem. The rib web cutout will have a small effect, you will never want to to notch the rib cap strips, nor will you want to notch the spar. It all has to fit.
Look up and down the wing stations for more clues to the problem. Check other sources. Then design as best you can.
You can always test your design with sandbags to confirm the soundness of your work.
