Dual bowden E3D extruder with 20x40mm spaced mounting holes

This is a modified design of http://www.thingiverse.com/thing:829066. This version has mounting holes that are spaced 20mm x 40mm apart to make it much easier to mount to V-Slot Gantry Plates. The diameter of the holes are increased to 5mm to support M5 bolts for mounting.

EDIT: Uploaded a second version (v2). The new version has larger openings for zip ties on both sides plus on the support brace. The mounting holes are now large enough for M5 bolts. The openings for the M5 nuts have been en