I notice in your photo that you're not using the O rings on the top of the valve stems, along with the positive seals. That's a good thing, as it's possible to "over-seal" the guides and wear them out for lack of lubrication. I've seen that happen on several engines. Use one or the other- - - - -not both. I like to use the positive seals on the intakes only, as the exhausts do not have intake vacuum against the bottom of the guides. O rings only on the exhausts are plenty of sealing as long as the sheet metal deflectors are used over the valve springs.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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