My 78 bonnie had been fittied with after market, stainless-steel head bolts, on the outer four. They had allen-head, instead of conventional 6-point head. I replaced them this spring with OEM hardened steel bolts because one of those stainless bolts began to break, crack, seperate (down in the threads portion). Darndest thing I ever saw.
My trusty/crusty, mechanic/guru advised the OEM bolts as they were stronger than the stainless.
DUM VIVIMUS VIVAMUS
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