They require one tiny screw hole drilled per tuner but they go in simply with no issues. I just put a bit of wood putty in the old holes you can hardly see em. If I ever sell (not) my Talman I can easily put the original tuners back on and it would hide the drilled hole. Be sure to center the tuner shaft when you mark your drill hole. NOT rocket science to do it. The drop-D extender install is only slightly more challenging.