Haven't gotten very far and already have a question. On page 11-03, figure 2 (and actually step 2, Machine countersink all #40 holes indicated in figure #2), an arrow points out seven holes to be countersunk. I would say they are to rivet the ribs in each location before skins are mounted. These rivets will be under the tank skins when the tank is installed. My question is shouldn't the holes on the bottom spar flange corresponding with the same ribs be countersunk as well?