My grandfather was James William (aka J.W./Willie) Tigert (1889-1975) of Daingerfield, TX, son of Louis (aka Lewis) Tigert (1854-1898) of Cookville, Titus County Texas. The ancestral branch that I have of Louis Tigert goes back about 10 more generations to Thomas McTaggart, born abt. 1565 in Ireland. I got a huge boost in my family tree by merging the johnson-harper GEDCOM file with my own.
My branch for Benjamin Franklin Tigert is a little skimpy, but the kinship chart shows him to be my "Half 2nd cousin twice removed" (whatever the heck that means!).
I'll be glad to send you an ancestral chart (Microsoft Word), or an FTW file, if you'd like.
I'm also interested in what you have, as I am still filling in many different branches on my own tree.