CWC 540 233 is the camshaft core number. You will have to pull the camshaft to get the number(s) or letter(s) off the end of the camshaft to identify what the grind is. CWC is Campbell, Wyant and Cannon. The foundery has produced millions of camshaft cores. Camshaft grinders buy the cores then machine them to whatever specs. Aftermarket camshaft companies and automobile manufacturing companies, including Pontiac, use CWC cores. It is now called CWC Textron.
You will have to compress the valve springs the amount of lift and check if the spring is binding. Maybe take off the other rocker cover and pull the engine through to check what the clearances are.
How much if any play does the valve stem have in the valve guide? Is the seat damaged at all? Is there signs that the valves were floating? Is the pushrod bent? Is there wear in the rocker cup or on the ends of the pushrod?
I'd say at the least you'd have to remove all the valves and springs then inspect the head, valves, springs, seats, keepers etc. for damage.
