This design is intended to be compatible with boards that have mounts for larger lens on them like the Arducam 5 Megapixels 1080p OV5647 Camera Module with CS Mount Lens (that I have). The board must measure less than 36mm and have mounting holes 29mm square.

For the three prong version the hex opening may be slightly undersized for some bolts. I pushed into place with a soldering iron on the bolt head to get a perfect fit. The ones I've printed work well with the injection molded accessories my knock-off action camera came with but most printable extension arms on here are a difficult fit and require some sanding to get the fit right.

Autodesk Fusion 360 links:
2 prong - http://a360.co/2tEw2Gt
3 prong - http://a360.co/2t7qemE
3 w/ mount side cable slot - http://a360.co/2tBZu13
2 w/ mount side cable slot - http://a360.co/2sJTela

Creality CR-10

No

Yes

Simplify3D put in supports for the bolt hole in the GoPro mount bracket. Some printers may be able to bridge that without distorting the opening too much. I just let the slicer do it's thing and printed the supports. They may not be necessary.

I printed .2 height 4 layers top, bottom, side with 30% infill. Probably overkill for most use cases but mine is bolted to an arm attached to the traveling print bed.

To stress relief the ribbon cable, feed the flat cable through one of the loops and plug into the board before you screw the board down to the mount.

I used 4 M4 socket head cap screws to secure the board by screwing the threads directly into the plastic. You could use M3 hardware with nuts on the back if you like.