Any kind of penetrant that you can get down the valve guide would be good. Just not WD40.(but if that is all you have..) Just realize you may eventually dilute the oil and need to change it after you get it unstuck, and don't rev the wiss out of it. Does it have a side cover plate that you can get access to it? Remove the exhaust manifold and look with a scope, spray down the guide directly? Get it on compression stroke and push it down physically?(just be gentle if you can reach it with a bar or blade). Diesel in the oil and just let it idle?

Any of these could work. Is it really that hard to get the head off?

ETA, just found pics of it online with a side cover to access the lifters for adjustment. May want to take it off and verify problem and see what can be done to free it up. Also look like you would be able to get penetrant down the guide with the exhaust manifold removed.
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Last edited by calikooknic; 02/10/14.

Sean