With all the old wiring and related items out of the way, we could finally get to installing the Highway 15 kit. Since the fuse panel isn't pre-wired like the Classic Update kit, we routed all the wires first. | 
Like many companies do these days, American Autowire makes it easier on the installer by screen-printing each individual wire with its intended use. With this in mind, if you find yourself using a particular wire for something else, make sure and mark your supplied schematic with the appropriate notes. | 
To keep everything nice and tidy, the wiring for the front and rear of the truck was routed down inside the cowl panel with the fuse panel mounted on the upper portion of the inner firewall (the battery/ignition wire was run along the dash). Doing this may be a bit more time-consuming, but the end result is worth it. |
The bulk of the wire runs out through the bottom of the cab, as shown, using tape instead of tie-wraps to prevent snagging within the cowl. | 
A section of protective wire loom was installed over the wire at the exit point once everything was pulled through. Then, the front and rear sections were separated and secured before being covered in loom as well. The front portion will be routed outside the engine bay, behind the inner fender panel. | 
One of the difficult aspects of running everything hidden and loomed is making sure you provide feeds for all your sources. Knowing that a Vintage Air unit will soon be installed, we made sure to include wiring for an electric fan. Also shown bound up, are the horn and fog lamp wires; the two wires running up along the radiator support are for the headlight. |
If you're upgrading an old 6-volt system, make sure and grab the appropriate lighting components, including the headlight bulbs. And don't let the three-prong connectors of an old 6-volt sealed beam fool you--check the light itself! | 
The ignition switch provided in the kit is a standard four-post type. If you intend on keeping your truck's foot-activated starter switch, simply omit the starter feed wire. The stock foot switch will still get constant power from the battery and your new key switch will activate the coil as before. |  |