Fitting
Tap the screw towers on the bottom half with an M3 tap, then use 13mm M3 screws to attach the 2 pieces together. If you don't have a tap, drill out through the base and put a 16mm M3 all the way through it with a nut on the back.

Post print
The centre camera hole is a little tight, if your printer under-sizes things you might need to run a de-burrer around it.

Coming soon
There are slots on the back for the mount which at the time of publishing I've not built yet, but I'll add it when I've done it.

Hope this helps someone out!

Best

Matt