Another data point on the KZ shims. The Honda shims, cb750 DOHC, did not get softer as the metal came off. IMO it's worth a try if you've got no parts on hand and if you can recognize when you're getting into the softer metal.
I'm CURSED with this 1100 missed ANOTHER block on ebay by $1. I really want to have here ready in two weeks so I can shakedown for a week and then take on a 600 mile RT.