QU-BD One/TwoUp Extruder V11 with video

This is a replacement extruder for the QU-BD One/TwoUp printer. It replaces the wooden parts, and holds the hot end.
It replaces the wooden extruder and screws to the kit's gantry mounting parts. Or even better, it works perfectly with http://www.thingiverse.com/thing:223327 which is a one-piece printed mount plate that clips onto the linear bearings!
It can be used two ways.

If you have a large format printer, you can print UpGrade.stl, which contains all of the parts of the extruder a