72 engine harness question

I just got my new engine harness from Bill and Rose Evans and I have a question. At the alternator end of the harness there are the 3 connections for the alternator, the round push on connector for the temp sender, but there is a BLUE wire with a FLAT push on connector on it that I have no guess at where it goes......unless it's for the A/C compressor (if equipped)....but I really doubt that's what it's for.

SO....any clue where it's supposed to go?
Author: admin