I really like the original design, but wanted to switch over to a leadscrew driven Z-Axis i remixed these parts to fit the 8mm leadscrews that are available on eBay.

The distance from the center of the Z-Rod to the center of the leadscrew is 17mm (i think Prusa original distance).
The mounting holes for the Motor are switched to the back, so the motor can be mounted on the front.
And overall i made the part on most of the sides 1mm smaller.

The Belt-Tensioner is a Remix of "Prusa i3 Hephestos by bqLabs" and is modified for a better fit into the X-End. For that you will need two 624z bearings with an M4 screw. For the tightening mechanism take a M6 Hex-Bolt.
With this idler mount you won't bend your z-rods when tightening your x-belt!!!
The -1mm version has a bit deeper holes for the Nut an the Screw, but first has to be testetd if it is stable enough. The Normal Version could touch the Leadscrew.

I didn't mount it yet, but the first testprints seem to be good and don't need further modifications. So, feel free to test it. As soon as i have mounted the parts, photos will follow.