Best way to run wires from bed to engine bay

I have some lights in the back near where the bed meets the firewall. I need to run that up front to the engine bay battery area. What's the best route to take?

 

Inside the frame rails.

 

Yeah what he said, I have a air compressor in the bed and ziptied them inside the frame rails attaching to the existing lines for fuel and what not. With that distance just make sure you have the right gauge wire, no problem

 

Thanks everyone!

 

I ran a circuit from the bed up to the fire wall, it's tough avoiding being near the manifolds if it's a V6. After seeing the factory wiring in the same area with it's heat protection I wrapped the wires in foil tape, it's not as nice as the factory did it. I were to do it again I'd start at the front and install the heat protection prior to trying to do it laying on my back under the truck lol.