Cam End Plugs + Stripped Valve Cover Threads

In the absence of a specification, I start with the middle bolts and radiate outward. Just my own preference.

There should be a sequence in the manual but if not the rule of thumb is the same as ahead, loosen from the outside in - tighten from the middle out (if f there is any distortion tightening the ends first will prevent the middle from pulling down)

On the Z1s and KZs there is no specific tightening sequence for cam cover bolts.  There is one for the cam bearings though, and they are the same size.  From memory I think the general torque spec is around 95 to 110 inch lbs, but like others who have chimed in I don't go that high.  I normally go about 75 inch lbs.  This is because the head is 50 years old and has seen a lot of bolt removals over the years that tends to wear down the threads over time.

One thing not mentioned yet is to clean your thread holes thoroughly.  I blow compressed air into them.  Also clean the bolt threads to make them slip more easily into their mounting holes.  I use a wire brush.