Loop the belt around the Right X Mount bearing with the smooth side against the bearing towards the X carriage

Take your X Carriage Front Plate and feed the belts through their openings. The "lower" belt feeds into the left and the "upper" feeds into the right.

Be sure to route the belt through the back of the Front Plate pulling out any slack in the belt loop.

Secure the Front Plate to the Top Block and the M3x27 standoffs with 4x M3x10 socket head screws.