X Skis, X carriage replacement option for all Mendels

UPDATED.

An option to replace the X carriage on Mendel RepRaps.

*Variable length between bars.
*Variable width for extruder mount, or other tools.
*No more need for fitting things in the X carriage holes.
*NO GLUE, but you can use glue instead of set screws if you like.
*Hole for an LED to point down towards your print, and a channel to run the wire.
*Less Plastic than anything I've seen so far.
*More visibility where the extrder filament drive meets the hot end.

Pictures show the