I mounted my jig to a piece of plywood about 16" x 20" and then I clamp the whole thing down to the workbench when I use it.
I'll take a couple pictures tonight and post them here tomorrow.
I mounted my K-3 to a piece of plywood that is wide enough for the Kreg tee track I bought to fit alond with two support-stops on each side. I cut the tee track in half rather than notch the jig, I didn't want to weaken it's structure.
This way I can support a wide panel, and stop it if I feel the need for exact hole placement.
I then hang the plywood/assembly up when not in use, and clamp it to the bench when in use!