Positioning of the end stop switch block is critical. These switches define the XYZ coordinate of the printer system and the firmware expects it in a certain spot in order for the auto levelling system to deploy and retract the mechanical probe correctly.

Place the tail edge of the end stop switch holder 60mm from the edge of the extrusion.

Conveniently, the leg of the vertex is 60mm; use one of the vertex legs to measure and space the end stop holder.

Lock down the holder securely with the 2.5mm hex key.