About this 3D model
This is two Wade extruders joined together. The mounting holes from the second extruder have been moved, and they're just a few mm off being joined by the centre hole. This is so that the pair can be mounted across the x-axis rather than along it without hitting the standard Mendel X drive belt. You will need to use the collared drive gear as few motors I found had shafts long enough. This uses mendel.conf and mendel.inc from http://www.thingiverse.com/thing:2192