I have a 96 Cheyenne Std. Cab that came from the factory without a stereo. Luckily, Chevy included the wiring harness that will make installing a head unit pretty straightforward. But, no speaker wire has been run to the doors or rear pillars. Does anyone have a diagram/instructions/videos of how to run the wires? I'm pretty intimidated by getting the wiring to the rear pillars.