I have the 10w Creality laser kit to add to my Ender 3, with a Sprite Pro extruder. However as i use linear rails it couldn't just hook on.

So I made this spacer to give it some more stability when mounted to the 2 screw points on the carriage.

For if you would rather design your own the hole centers are 14mm apart. On this carriage they carriage mounts are 6mm wide and 5mm deep