roof rack

It's my first post here, and I haven't seen a right place to address the following, any suggestions? After selling a few Gen2 rear side window Molle Panels for Gen2, just a couple of Gen1 panels sold too, but I think there should be more interested Gen1 people out there! The above is for...

I have a roof rack but have been thinking about the storage bin and a light bar. the storage bin I can probably figure out. the light bar how do I run the wires? harbor freight has a 40" for $90. I know stupid I just got my first one and love it.