It doesn't hurt the cylinder head, but be sure you don't get the light-duty eye bolts that aren't welded or forged where the loop joins itself. The thread size is 1/2" X 13. I like to use heavy-duty forged eye bolts, if they can be found with a long enough thread to duplicate the length of the head bolt. Otherwise, be sure to weld the eye into a continuous loop before putting the weight of the engine on them. It's also a good idea to weld a heavy flat washer just below the eye so the eye bolts can be turned down snug against the head.
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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