Ed, my straps-ons are much simpler and aren't really a frame. Picture a curved plate of metal that is shaped to fit the tube. It has a welded on piece of pipe/tubing/oar lock receiver and slots on the top and bottom for straps that go around the tube. There are two plates, one for each side of the boat. They were sold Scadden years go before he started using the WM-type glue-on oars. I haven't tried them on the WM yet and I'm not that the curvature is the same but I'll checkand post photos if they look like they will work.