Headlight wiring GMC

I was roughly connecting my headlight relays to make sure everything was going to work and I found two light green high beam wires coming thru the firewall connector to the left rad support area. I guess I just haven't seen the second wire on any of the diagrams I've looked at, it had me wondering for a minute. 12 volts on both wires with the high beams on. I suppose I'll stow the second one.