door frames are rarely parallel to the door surface; ergo one needs a square to bring them in alignment. A Dremel was handy for getting the wood levelled small bits at a time using the square as a guide. Dremel was also used for boring the door with the circular cutting guide. Not a locksmith installer, but result was excellent! Love that this lock self locks and only uses a very short electric pulse to unlock, because I only have signal wires for an alarm system in place and anything longer than a sec would fry them; Instead of a 12V supply I used a 24V (to limit current over wires) and a non linear step down to 12V. Passing the current over from the frame to the door was tricky, because I hate visible wires or cutting the door, so made a 3D part to surface mount cisa-like spring loaded connectors. Looking for cylinder guard now to protect it from pulling and drilling. Will use shelly access control for electronic control.