alternator wiring ( 3 Wire )
 

Hi guys,
Certain this has been addressed before but just cant find it. Working on my son's rat rod with every varied part that worked used to repair by previous owners. As I know alternators from my Oldses, Large red wire to positive stud on back of the alternator, and a two wire pigtail into the #1 and #2 male tabs on the outer edge. Here's the concern!! Rather than a stock pigtail, it was replaced with two black wires and crimp ends to attach. My son did not note which wire went to 1 or 2. Please educate me as to #1 and #2.

Thanks,
70 ctls