Parametric Z endstop mount and arm for Prusa i3 rework

Z axis endstop mount and adjustment screw arm for a Prusa I3 rework with an extra-long extruder heat sink.

The endstop mount is designed to be attached to one of the Z axis motors, and the arm is designed to be attached to the Y axis motor above it.

Parameters allow the arm to be adjustable roughly 10mm on any axis so that it can precisely touch down on whatever model of endstop you use.