This is a remix of a gopro mount and a molle tab combined to create a small GoPro mount for an NVRT or knockoff NVRT chest rig, like the pictured one I use for speeddart competitions. The end result is that the GoPro is mounted on your shoulder.

Print as oriented in the file, with supports for the molle tab but not the GoPro portion. You'll need to carefully use a knife or flatblade screwdriver to remove the support from the molle tab.