If this would be for the Genz (blue) box, I make and have kits available if you are interested. My kits do fit the blue box without doing any modifications or drilling any holes.
I 3D print mine out of PETG, but UHMW would work well too, could use a cutting board for material, would be the right thickness.
Here's a pic, if it's any help. If you pick up those holes on the gimble mount and use those to mount your arm, you can get enough length to do it all in one piece. I've seen aluminum, and wood versions too, but I'd think you could shape a cutting board pretty easily with a jig saw and dremmel.
