For those interested, I finished making and replacing the stock extruder on my cube with an E3D V6.
All in all I can max out Z at 133, so I lost a few mm, but it works great.

Check it out here:
2018-04-02 - Updated Version: I quickly realised a few problems with the first design and have since updated the following:Filament Feed AlignmentSpring Tension Placement - old version caused the ...