Take 2x Y-Axis Belt Lockers and Belt Locker caps. Using 4x M3x10 socket head cap screws partially attach the caps to the lockers.

Make sure the rounded end of the cap is towards the side where the belt goes.

Secure the Belt Locker Assembly and 2x black spacers to the bed plate using 6x M3x14 socket head cap screws.

Note the position of the belt lockers and endstop bump stop. The side with the bump stop will go towards the rear of the printer.