I found some detailed tuning information on a forum that is similar to what you have read in the tuning manual from Mikuni, but this additional information may be of great help to understand more of how to step-by-step tune your engine with these carburetors. This is for watercraft, but the technique is the same for us.
I copied all of this to a MS Word .doc and can be accessed at the link above. This is 18 pages and includes three discussions.