Jerod,
I'm in the process of converting my 1 wire to 3 wire and have found a lot of good info on this site by searching the archive. The is my first time so understand I'm not an expert in any way. I've attached a diagram that is available in the archives showing the power wire going from Alt to horn relay/bus bar. That is how mine is set up. Currently the red wire goes from Alt straight across to drivers side fender, too close to headers. I'm going to wrap red, white and blue wires and run them next to intake manifold to firewall, across to drivers side, under fender to horn bus. If you go this route you'll have to add wire to make the run.