ok so my truck has all electric switches for the doors and the windows. the windows roll up and the passagener door will unlock but the driver side door does not unlock electricly or with a key i took it apart and there is no electricricals to unlock the door it is all manual. So my question is can i just buy a solenoid and would it fit up in there or is there more to it that i will need the door has the harness already. thanks.