I have finished revising this to fit the GeeeTech prusa i3 with 21 mm spacing. This came out perfect. WELL DONE!! I like it. I haven't printed with it, but I love it. I think it looks much better. Just waiting on a new X limit switch.
On my version I added the Z limit screw to hit the switch and even revised it for lead screws. Will post soon, was also part of a complete Bowden extruder conversion that I made.