After studying a variety of DIY ideas for slow motion controls, I came up with my own pretty simple design that only cost me $110 in materials (plus tax). Once I had all the parts collected it only took me a day to assemble it on my Z8 Zhumell. For the azimuth drive I pretty much copied other direct drive systems I've seen online, but I used a monopod to create the altitude arm and attached with bimini hinge brackets (boat awning deck hinges). It works like a charm. Will gladly share my parts list, assembly photos and notes with others.