Could be....one wire does go directly to a 12 volt source, this would be for the 'unswitched' circuits. The other one goes to a 12 volt source through the ignition switch. this is for the 'switched' circuits.
A simple test with an ohmeter would verify which one is which. Circuits like lights, brakes, horn would be common to unswitched wire. Oher circuits like radio, heater would be common to the switched wire. If no fuses are installed yet, be sure to make the ohmmeter check on the feed side on the fuse holders.


Six volt guy living in a twelve volt world