This is a install guide for all Y kits the images are reference and will be different for each printer 

Step :1

Remove all stock components from the Y axis extrusion so the extrusion is as shown below

(note: CR-10 and larger style not shown but the concept is the same.)


Step :2

Remove the extrusion hold down screws on any smooth faced Y extrusions

(note: on the S1 & S1Plus leave the rear  bolts installed as shown below. on the CR-10  or larger printers remove only the front and rearmost bolts leaving the center bolts installed)


Step :3

Install Y axis kit on top of the extrusion and secure 

T slot extrusions it is best to preload the included hardware and Tnuts. Some kits will include 6MM aluminum  spacers to raise the kit up for clearance.

(note: on the ender 3 the single rail kit installs by (3) M3 SHCS through the rail mount holes of the rail)


Step :4

Install the motor and the limit

(note: the motor drive gear may be too high and some motors gears need to be pressed down to get the belt running parallel this is possible with a socket and some pressure but the easiest way is to replace  the motor with a D shaft stepper and a adjustable drive gear.)


Step :5

Install the bed and level

(note: the printers home offset may need to be adjusted you can learn how to do that here)