Printrbot Plus V2 upgrade extruder

The original laser cut extruder on the Printrbot plus is very problematic. It is big, heavy, hard to load up, easily to misalign filament and the passage below the hobbed bolt is too wide, causing frequent filament buckles and jams for me.

I'm aware that this is useless to 99% of people here but I've spent some time adapting parts of my mk5 extruder with a derivative of an extruder found on Thingiverse to come up with what I hope is a vast improvement.

Fully illustrated step by step instructions in the link:

http://www.thingiverse.com/thing:153583/