7 GoPro 360 Rig

I'm looking to do some 360 video test shooting so I downloaded a design from GrabCAD here: https://grabcad.com/library/gopro-7-cams-hd-rig-1 and got it printed on the Uni's Makerbot.

Just got it back and it's looking good (garish colours aside). I Just need to figure how to put it together and come up with a solution for a tripod mount. Thinking some M2 thread, bolts & glue for joining it, but I'll need to counter sink the holes and I'm a bit nervous about drilling or melting it.