1965 Dodge Dart Charger convertible

I think the ones i have might be body bolts with a wider washer. Your needing the engine bolts with smaller outside diameter washer. I am guessing that valve cover bolts from even slanty engines from around 1964 would have SEMS bolts with that style head, as they were probably advertizing their company on the bolt heads back then. I bought a huge bolt lot from RatRodAl from a bronse 67 fastback he stripped, since my sons 69 notch didnt come with any bolts as it was a half stripped out car. As i was weeding out the really bad bolts and putting the rest in evaporust to clean em up i saw a few with that marking. I found one marked with 67 bronse metallic paint, I thought it was unusual but maybe not as on the assembly line they probably have huge bins of hardware for assembly, and that one may have been in the bolt bin until it was grabbed and used in 1967. I believe by 67 they were marked with an S or an E, and had 3 dashes, and sometimes nothing marking the bolt head. Some by late 60s early 70s had a mark that resembles a boat anchor on them along with 3 lines or dashes.