Metal Bowden J-Head Mount w/Fan for One/TwoUP

This is a remix of dieck's excellent E3D V6 mount. I modified it to accept a 40mm fan and to fit the OneUP/TwoUp extruder bearing holders by Ionuf and Rcaslis.

I included the .scad file and an STL file of the entire assembly (don't print this one - I just included it so you can use Thingview to inspect it).