On the left hand side you can see the edge of the base I made for the planer to slide against. The ply is placed in from the right and secured, then the planer is pushed forward to take the first cut. As each pass is made, the left side drops the depth of the cut until the runner is resting on the work surface.
On the right hand side of the attachment, you can see the runners that ride on top of the ply and the shims to get the proper angle.
I had thought about some other methods but I already owned the correct model planer so this is the route I am taking for the ply.
