Remove the negative cable from the battery for safety reasons.
Black/orange wires get taped up out of the way and not used. Do not remove or mangle the plug on the end of the wires.
Small 3 wire used as is, no changes. It plugs into the same connector on the new alternator.
White/black wire on the plug where the Black/orange wires connect gets insulation stripped from it. Splice another wire onto it to make a Y. Solder the connection and use heat shrink tubing on it to cover the splice joint. Crimp a female 1/4" push on terminal on the new wire or use a connector from an old wiring harness.
Connect the fused 4 gauge wire to the alternator and the battery side of the starter solenoid.
Plug the 3 wire plug into the alternator.
Plug the white wire you spliced the into the little tab on the alternator.
Reconnect the battery negative cable.
Wiring is now finished. Check to make sure it is all neat and clean and everything is out of harms way. Start the car and check your voltage.