I am Cleo Mott Fnk. My research has been as follows: Charles Noble Mott 1887 Indiana to 1963 Illinois; son of Asa B. Mott Asa B. Mott 1861 Tennessee to 1944 Illinois; son of Amos Travis Mott Amos Travis Mott 1823 Tennessee to 1892 Indiana; son of Asa Mott Asa Mott b: abt. 1799 beleived in GA to 1825 Alabama; son of William Mott (no known middle name) William Mott 1765 either N or S Carolina, lived in GA, to 1838 Mississippi; son of Joseph Mott Joseph Mott 1745 N Carolina to 1787 GA
The above relationships are proven through legal documents.
Now: There is a land sale recorded in GA and the will of Joseph Mott also recorded in GA. Joseph mentions only one son in his will and that is Nathan. I think I have seen records showing Nathan having a son named William A. Mott. If this is the Wm you are looking for the "A." could stand for Asa.
Nathan's brother Lovelace had a son named William A. Mott also. Lovelace lived in Georgia, Alabama, Mississippi, Florida and I heard in Misouri also.
My gggg grandfather William's son Silas had a son named William (A. ?)Mott. Silas lived in GA, TN, Al, MS.
If any of this information helps pinpoint information and you need other help please contact me at firstname.lastname@example.org.