When installing Creality's Official Ender 3 Series X-Axis Linear Rail Kit on the forward facing side of the X-Axis Structural Extrusion, the X-Axis Limit Switch will need to be moved outward around 9mm so it will still function as intended. There are a few custom methods of accommodating this requirement (various spacers) but they all require longer screws to reach and secure the X-Axis Drive Motor.

This kit completes Creality's Upgrade Kit, with the parts needed to complete the installation.

With this kit you don't have to spend additional time printing spacers, as well as shopping for screws and likely purchasing quite a few more screws than you really need to complete the upgrade. I had to stop the installation until I found what was required, and since the printer was disassembled, I wasn't able to print any parts with it.

1. A longer X-Axis Stop Switch Cover or Housing which places the X-Axis Limit Switch at the correct location so it makes contact correctly and functions properly.

2. Four (4) 50mm long screws that reach and secure the X-Axis Drive Motor.

I don't know positively how many of the Ender 3 Series Printers this will work on, at least the Ender 3 and the Ender 3 Pro that have the same style plastic cover that holds the X-Axis Limit Switch.

You may need to flex the end of the legs a little to get them to line up with the threaded mounting holes.