After taking counsel from my bettors I changed the O-rings (#9 in the picture) on the left head spark plug tunnel. It was easy to do with the help of a set of dental picks from Harbor Freight. I used the recommended O-ring grease but did not try the three-bond. I am keeping that in reserve if this does not take.
Everything was carefully cleaned and scrubbed before reinstallation and I hope it stops the annoying weeping onto my left boot.
Interestingly the replacement Stucchi crash bars allowed me to remove the valve cover with them in place. With the originals I had to loosen them to do valve adjustments and such.[You must be registered and logged in to see this image.]