On the Sabre's rear cylinder bank, there is a spacer, or "rear cover base",
between the cylinder head and the valve cover. You can see the second
gasket line demarcating the division. To remove these parts,
separate the two from each other while still in place, then remove
one at a time, from the left side (shown). There isn't enough clearance to
remove both together. Thanks to Johan Ju for this photo
in which the shims make the separation obvious.
The valve cover has been removed from the rear cylinder bank.
You're now looking at the right rear cylinder head.
In this example, we will be adjusting the clearance for
the left rear exhaust valve pair.
Note that the right rear exhaust cam lobe shown here is at full lift.