[s-cars] Valve Cover Gasket

[calvinlc at earthlink.net]

What is required to be removed to replace the valve cover gasket?  I am
looking at the gasket now and trying to figure out how the camshaft sprocket
is sealed where it exits the valve cover.  Also, is this where the 2 blue
"half moons" go?  It appears as though there is a large half moon shaped
piece in the gasket itself as well.  Thanks.
--Calvin