Sometimes you miss something and find it later and say, "YEA", or "How dumb was that!" I'd always figured that my head gasket was weeping because of where I was finding the oil dribbling thru the head fins. I knew also that the tach cable was leaking. After spending an initial $2000 on this bike and having a mostly ruined back, I just wasn't up to the task of trying to pull a 170 Lb. Engine. The bike has always run like a banchi and my research showed that weeping from the oil return "O-rings" would'nt cause anything but a messy bike. I'd also heard from many that the tach cable seal was no longer sold or manufactured. That was wrong. My local Honda dealer carries it….even if made for the Dohc CB750, it's listed for mine. There are other on-line sourses for it too.
Anyway, after finally replacing the tach cable seal, I've discovered that my head gasket is NOT weeping, so YEA!, or How dumb is that? Now I'm spending some time cleaning the bike, and I guess I'll have to paint it, too, considering I've put nearly 30k miles on it this way.
Oil from inbetween the fins can just be the tach cable seal.