I looked at the plastic guide No. 6 and oiled the heck out of that. I also oiled the heck out of No.1A, the nylon cord that attaches from the spring to the hinge. I also soaked the spring No. 1 in oil too. And guess what the sound is still THERE!
All parts are in good condition, I really thought this would be simple, but these howling closing parts makes me scratch my head. Any tricks on how to quiet this would be greatly appreciated.