Well here is my latest bit of handiwork. A bit of 25mm Aluminium tube, the a bit of 25mm dowell that I reduce in diameter for the first couple of inches and inserted and held in place with screws. Drilled a 31/64" hole in the top, filled with araldite then drppoed in a 1/4" bolt upside down with a couple of nuts to make it snug. This enabled me to attach a cheap ball head which then attached to the cradle for the AN unit. Attached to the rocker with a couple of saddle clamps and a right angle bracket.
Good design Malcolm. AN on a stalk needs to be mounted on a ball-head for use on a dob. In the paint section of Bunnings there is a neat little ball-head tool that can be turned into part of an AN mount.
I made an Argo stalk for my 16" lightbridge out of scrap steel. Never found a need for a ball joint though. I just welded the necessary mounting parts at a suitable angle. It is held onto the rocker box with 1/4" wing nuts.