Elderly bolts can, and do stretch. I'd suggest replacing those rocker stand bolts with 3/8-16 Allen head cap screws, which are available on Ebay in a wide variety of lengths. Fastenal will probably have appropriate length new studs for the valve cover attachment on the 216/early 235 engines.
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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