Prusa i3 Zaxe endstop (Makerbot 1.2) holder for tuning screw

I printed this : http://www.thingiverse.com/thing:81208
But I didn't find a part for placing the Makerbot 1.2 endstop.
So I made one. It places on the alu frame.

Please refer to instructions for assembly.

This is my first 3d printable part... done with openscad, that I find more simple than others CAD programs. This is also my first release to thingiverse. Please advise me for improvments.

Best regards,
Gautier.