Do you have the extended fuel tanks? Be sure you are using that manual if you do. They shipped me the standard manual when I had extended fuel. Also.... BE SURE YOU ARE USING THE DROPBOX MANUALS AND NOT THE PRINTED ONES (without at least comparing them). There are many changes Mitch did to the manuals recently which are not reflected in the printed versions (and some pretty big wing changes). You should use this link to go to the links for dropbox (not any that Mitch originally sent you probably). If you use this link and then download the manuals, etc., you will be assure of getting the latest version with current changes.
https://www.dropbox.com/sh/umnw9kf8b...ZfztWOw8a?dl=0
If you have extended fuel, the rib #2 is not a full rib but will be a false rib installed later under/between the 2 fuel tanks. #13 is outside the drag wire area so don't worry. Just be sure and do ONLY what the manual says and WHEN it says to do it. Ignore anything else in the drawings that may show up during that step as they use generic schematics and photos that may show other things installed. Just follow the manual step by step and only do what it says to do and when it says to do it and you'll be OK.