While looking over  your page, I was struck by your ball turning set-up as being the best/logical/least complicated one I had run across, and thats what I'm finishing up now----waiting on the carbide inserts to come in to finish up. I designed mine to fit my 12x36 Birmingham, so its a bit changed,  (including the clip on bottom, instead of screw) I've including a couple pix of my version.

Thanks Bill, Great Job!