Long of Talladega CO AL NC

I have been looking for this family for the past 18 years. It has a been a huge brick wall. My G-G grandfather is Alfred or Alford Long, b: 1803 SC d: bet. 1866 & 1870. He married Margaret Nelson (b:1 Nov 1823 d: abt. 1867) on 16 May 1840 in Tallapoosa Co., AL. I tentatively have Alfred's father as Thomas Long (b: 1771 d:??) and Mary ?? (b:1775 d:aft. 1860). I believe Alfred had brothers Allen (b.1815 SC d.??) and Thomas (b.1817 d.??) and sister Elizabeth (married Isham Nelson) Alfred and Margaret lived in Talladega and later Bluff Springs, Clay Co., AL. I can find nothing to prove the link to Thomas Sr except the name patterns and I can find nothing concrete on Thomas Sr and Mary before they appear in 1850 census in Talladega Co., AL. Have done DNA testing but no definitive links yet. Would love to connect with anyone who could point me in the right direction.