The Zachariah who was born ca 1758 and died 12 Oct 1843 married Rachel Peller. They are buried in the Peller family cemetery in SC. According to the records for SC RW soldiers ie-Bounty Land grants, Zachariah is the son of Daniel Blackwell. This Zachariah did have a son named Zachariah as well.
It is believed that Daniel is the brother of MY Joel & his brother,Isaiah Blackwell as all three are documented in Orange Co. NC in the 1760's before moving south. As far as I know they are NOT related to Rev. Joel Blackwell who was about 20 years younger (b. ca 1753) and came later to NC with his brother, John. Rev. Joel has been mixed and matched for over 60 with my Joel who died in Rutherford Co. NC in 1821.