I found one on Thingiverse for my C7. He had a C5 and C7 version. I used screws to mount it.
Found the link. Has a desktop and wall mount version for C4, C5 and C7
Plus, if you try out one of the mounts you can reach the creator to make changes to the design, if you are not comfortable working with OpenSCAD yourself.
Would anyone out there be willing to print a few of these up and ship them? I will happily pay for your time / effort / material / shipping.
PM'd you.
