So the flaps have a two foot long axle rod on the hinge line. The rod has to be guided thru the wing and flap hinges to secure them for operation. But how are you going to find the three sets of hinges with the flaps closed up on the ends? Guides of course.

Picture one shows the innermost guide - it finds the first hinge. Next guide is in the flap lever. That one sends the rod right thru the middle hinge and I found that the rod easily finds the last hinge from there. Second picture shows the only clue there’s a rod in there at all - the insertion holes.

I wonder how Rob and Detlef tackled this. . .hmmm