Summary

This is an improved X-End Clamp for the allready improved X-Ends by nophead.
Together with the Z-Min-Endstop mount you can use a M4 screw to adjust your Z homing position.

Instructions

You need:
Vitamins:
1x M4x40 screw
2x M4x25 screw (depending on your Frame thickness)
4x M4 hexnut
2x M4 hexnut (optionally)
4x M4 washers
Printed Parts:
1x Z-MIN-Enstop-Mount.stl
1x X-End-Clamp_Z-Endstop-Screw
Instruction:

Insert two M4 nuts in the X-End-Clamp-Z-Endstop-Screw and screw a M4 screw in it.
Exchange the original x-end clamp (x-end idler side, near to the frame) with the new one.
Drill two 4mm holes in the frame, near the left motor mount (see picture).
Attach the Z-Endstop-Mount to the frame, using 2x M4x25 screws, 4x M4 washers and 2x M4 hexnuts.
Attach the Endstop to the Z-Endstop-Mount
Optionally (as seen on the picture):
Screw 2x M4 hexnuts on the top of the M4x40 screw.

Improved Z-MIN Enstop Mount and adjustment for Mendel90 with improved X-Ends