Running wires into the cab

So who had done this...can't find a straight answer as to where to run them. Putting on lights in the rear of my Yakima Rail Grab.

 

Sorry I don't know what that is, but there are many entry points into the cab. Rubber plugs under the seats and in the firewall are the most commonly used for these type projects.

 

I guess what I mean is if the lights are mounted on a rack, up top, what is the best way to run the wires into the cab...like out of sight. I don't want to drill.

 

Some have run wires down the windshield molding, like they do for the LED bars. Only other way would be to drill.

 

OK, that's what I'm looking for....