My strongback is overhead in the garage today and I don't think I have any good pictures. But my external strongback is made up of 1'2 inch ply and dimension lumber making 2 hollow 'tubes' that are connected by 2x4's that slip inside and are screwed in place to join the 2 pieces together. The strongback, when assembled is very rigid on its own. I have 3 wheeled supports for my strongback that allow me to roll it out to work and back against the wall when needed. If you make a quick check of your setup after you move it you could probably figure out a way to shim it up as needed.