There are four wires that come off the back of the Motorcraft alternator. The only two we were concerned with came off the charging post. We simply took them off the charging post of the Motorcraft and bolted them to the charging post of the GM. We taped off the other two unused wires. Technically we should have upped the wire size from the charging post since this alternator puts out 100 amps, but it'll do for now.