Any tips for running wire behind the overhead part of the headliner? I have a load of 18ga duplex cable that I was going to use when installing my new LED cabin lights. What I am not sure about is how to securely attach the new wires to the old together so that I can pull the new duplex through. What I live in fear of is the wires detaching halfway through the run leaving me with no way to get wires to where the lights are. Suggestions?