The wheel I ordered for the head motor arrived Friday and I wasted no time installing it.
I got the wheel from ServoCity.com. They actually send you two wheels. In addition I had to order a 1/4" wheel hub to attach it to the motor shaft plus screws.
Video shows the wheel working without and with the head on. Another long awaited mile-stone reached.
It's a good thing I got a stronger tension spring. I tried it with the first one I got and it wasn't pulling the bracket hard enough for the wheel to get good traction on the Rockler bearing. Using a shorter and stronger spring fixed that.
I also received shipping conformation for the belt wheels with am estimated arrival time of "varies." God willing the wheels will arrive in time for me to install them before Droid-Con.