Gary has been able to repair and modify every instrument I've brought him. He has also modded all of them. He added a Fernandez Sustainer, killswitch and Vibra-Trem circuit to an old Telecaster replica from the 50's. He also added LED lights to the top of the case in my Trogtronic flight case. He even added a clip so I can still remove the top if I want to. The power pulls from the main unit just like any module.