Looking for Peter Williams Born IN South Carolina Died IN Jefferson County Missouri

My name is myrna Fairchild. i am trying to get past a brick wall that intails one of the hardest names to research, Williams. My faher was Robert Dames, His mom was Amelia Williams Dames, Her father was Silas Williams, his father was Silas Williams, his father was John Williams one of the founders of Jefferson County Missouri. I have Johns father as Peter, Peter was born in south carolina and died in Jefferson County and is buried on the sandy creek. I am so lost when it comes to finding the right Peter in south carolina.
My dad would say that his grandpa Silas would say his family where yankees. Not sure what to do with that.
HELP PLEASE!!!!!!!!!!!!!!!!!!!!!!!!!!!