OK, i have a toyota corolla 1995 and have bought a remote locking unit for it. the car has central locking but someone told me i need to buy a electric door actuator for the front drivers door because thats the door that you lock and unlock it from manually. Im a bit confused with the wiring though. I was told that i could wire this unit from the driver side door using the wires to the key switch.. but i cant get my head around it. as far as the actuators are concerned, do they operate on 12 DC to unlock and -12 volts to unlock (reverse polarity). also would all door actuators be controlled and wired to the drivers door? i cant find a wiring diagram for my car and im not very accurate with google.
please help

Thanks