Alt wiring questions

The painless system I got was a prf-50001. As for the moroso switch panel its a mor-74131. The alt set up is the one like in the diagram above. I believe its the factory set up that belongs on a 73 dart v-8. Like I said there was so much spliced in everywhere I couldn't really tell what went where. Is the 18ga or the 14ga wire watching the ignition voltage in the diagram you gave me? I also need to know what wire and where it connects to the fld part of the alternator if it matters.