There is/was a plan on the web for the practical types to make their own, which is what I did. Prior to that I bent & bolted up a bracket to evaluate the system & on the back of this experiment I made one to the pattern posted on the net. A couple of mods were made along the way but nothing that improved the original. The test bed item went through my hands last week when it became something else, had that not happened you could have had it with the greatest pleasure.
M