Bad picture, but hope it gives you an idea. I had to mount the retract assembly on another ply plate which was then screwed to the mount in the Roo. THe retract assembly was too small to screw to the mount in the plane.....hence.....the extra plate. The wheel collars you see in the foreground are what locks the gear down. I sure there is a simpler way, but the stuff was laying around and it works.