Prusa i3 MK1 Y-axis belt holder

After installing Y frame bearings mount (http://www.thingiverse.com/make:218651) I need to adjust belt holder height to new belt position. I reused idea of belt tensioning from http://www.thingiverse.com/thing:745934 and belt attachment teeth from original part.
Motor pulley and Y idler have different diameter, so the height of belt attachment is not same on both sides. Now belt is nicely in line with pulley and idler.
You need M4 nut and long M4 screw (at least 35mm)