Slide the GT3 pulley onto the shaft of the stepper motor.

The motor shaft has two grub screws. Make sure that one of them is aligned with the flat surface of the shaft and tighten both grub screws.

Leave a narrow gap between the pulley and the motor surface to avoid friction.

Insert a M3 Square Nut into the slot on the back of the x-motor holder using electronics pliers

The x-motor mount is now fully assembled.