This was a fun little project. Figured I'd share a couple findings here in case anyone is looking for ideas

I used an aluminum angle bar and a framing post strap to make the mount. It is mounted to one of the truck bed bolts. One of the steel frame tubes provides a tidy little pathway to the driver side rear wheel well for one of the air hoses. There is a hole inside on the bottom, near the passenger side, and another hole in the member below that allowing you to get a finger up there to fish the line around a couple corners.