Universal X Carriage for single and double extruder Prusa i3 Sunhokey

This is an evolution of my project http://www.thingiverse.com/thing:793689. The new universal X plate carriage is screwed to the upgraded linear bearings SCS8LUU can fit 2 different mounts for single or double extruder. It is very simple to change the support for one or two estruder through the two M5x16 screws mounted on the back of the carriage between the bearings without dismantling the carriage from the bearings. Are also included two types of mount for the cooling fan of extruder that you