Installing the KAVA Lite on your KAY3D CoreXY kit is pretty straightforward. But remember that if you're not confident in dealing with the power supply, please find someone that can help you out. Safety First!
Turn off your printer and disconnect the Mains
1) Remove the two bolts (two red arrows) that prevents your power supplys' terminals form being exposed. Connect your KAVA Lite's PCB cables to the power supply's red and black respectively.
Red goes to red. Black goes to black. Do not attempt to connect them in reverse polarity. The PCB will blow immediately.
2. Ensure that your power supply cables go to the correct ports (yellow arrow) on the KAVA lite PCB. Red goes to +, positive, and Black goes to -, negative. These should be indicated on the board but they may be small. Be sure to connect them correctly or your board will blow.
3) At where the green arrow is, if the wires are not connected, be sure to connect them to the KAVA Lite PCB. Next, take these two wires and connect them to your board. You'll need to connect them to to Signal and GND pins. Do not connect to the 5V pins on your end stop
4) If your have the stock hotend, you'll have to remove one of the bolts
5) Attach your new mount by screwing into the two holes on XCP-001/XCP-002
6) Next, you'll want to connect your KAVA Lite sensor itself to the mount. But before that, remember to loop it within the the CoreXY frame. This ensures your sensor cables do not get into the way of the running belts.
7) See the black plastic rings in your kit? Time to remove them and start by turning one of them into the threaded parts of the KAVA Lite
8) Next, you'll need the printed space in your kit
9) Thread the other black ring at the bottom of your sensor and now slowly move your bed towards the Nozzle. Your Bed should be physically touching the nozzle. If your nozzle is still hot, you should do it after your nozzle has cooled down