When I designed this layout, I figured I’d be limited to face structures that could rest on the small 1×2″ moulding at the top of my car siding knee walls. Of course more of these structures (including docks) would protrude more than 1 1/2 inches from the drywall. This in turn creates a bit of a problem when the shelf is rotated into vertical position as the portion of the shelf against the wall actually rotates up 1/4 to 1/2 inch.
Then I saw a post in another forum inciting that many modelers do not fix their structures in place on top of the benchwork surface. They float them so they can pick them up if they need or want to. Seams are covered with clutter, weeds, ballast, etc.That would solve my problem as long as I had a place to put them when removed from the layout. A shelf directly above would fill that need.
So I’m going to experiment with removable structures. Aside with dealing with the issues with face structures, this approach would also allow me to put some structures on the layout surface itself.