My William Taylor was b. c 1774 in Marion County, SC according to the 1850 Census, but is it is not necessarily correct. He had a wife named Hannah and a mother who was probably the daughter of George Lee of NC. George Lee's other children may or may not have been Mason and Sarah/Sally Lee (who married Blake Baker Wiggins). William had a son William (1803-1873) and a son Lewis (1792-1870) and probably some of the other Marion County Taylors are also sons, but I have no proof. I do not have any records of an Isaac.I am fairly certain that William came from NC and was probaby not b. in SC.
I looked at your website. The William Taylor you are looking for predates my earliest known William by about 20 years. It is possible there is a realationship. I will continue looking for more information and will let you know if I find out anything.
Thanks for the feedback. Sounds like there is not a connection here, but it is always possible that your William could be connected to my Isaac's brother somewhere up the line. One never knows if and when that breakthrough might materialize :-)