I had to revise the image post above, what a disaster
Sure little information on TCS and that. Some information, seems to be a mix but two senders on some trucks.
http://67-72chevytrucks.com/vboard/s...d.php?t=577620
Edit: From what the distributor told me #6 & #9 is for engine temperature sender, and they didn't alter the harness at all. Many opinions are the temp. gauge sender is supposed to be on the LH head. Seems to fit better with the sender on the RH head, though the wire jumps back over to the LH side on my other 402. I can't speak for correct on either truck.