Lockable ball socket v-slot mount

[Update 12/27/2018 2]: Fixed it. Re-uploaded the STL. Fusion 360 file: https://a360.co/2Td1Nlu

[Update 12/27/2018 1]: The STL file I uploaded might result in failed print. Fixing it.

I was looking for PS Eye camera mount for Ender 3 and came across with @usernameusername's remix (https://www.thingiverse.com/thing:3262776), which is based on works of @fedorsosini (https://www.thingiverse.com/thing:3147899) and @schemenke (https://www.thingiverse.com/thing:1079807).

I don't want to get ex