Email sent but I will post here as well...the hole in the wire loom you are asking about is for anchoring of the idle stop solenoid wire(blue). A white plastic push-in type fastener is taped to the wire and just pushed into the hole thus securing it. 1972 was the year Chrysler Plymouth started using the idle stop solenoid to help prevent run-on or dieseling of the engine after it was shut off during hot weather. I remember the plunger would always stick and have to be sprayed with a little WD-40 or a few drops of light oil. Do you have one on your car? I will post a close up pic tomorrow.........Dave