That Powermaster is a 2G styled alternator, but it's configured to work in a one-wire setup, so no need for the factory harness.
However, I'd recommend the use of a proper 3G or 6G alternator. A 3G uses the factory voltage regulator connector, you just need the single wire connector to the stator to splice on to it.
The 6G needs a completely new connector, but only uses two wires instead of the three like the 3G.
Both need a new charge cable run to the starter solenoid as the factory charge cable is not sufficient enough to carry the increased load. The use of a 175 amp Mega fuse in an inline holder is recommended.