Two x-carriage prusa mendel mod.

Based on buildrob (http://www.thingiverse.com/buildrob) aproach I want to create dual X carriage mendel prusa mod.
Original: http://www.thingiverse.com/thing:115885

It would require 2 carriages from part: http://www.thingiverse.com/thing:124255 and software updates done by buildrob to Marlin software.