You may want to find out where in Tennesee he is supposed to be from and check census records, and the census records from Arkansas in 1860 and 1870 to see if you can locate James C. Capps' family. The marker as Mr. Burke indicates may give you a clue as to whether or not it was the US or Confederate unit. Would age 43 been about right for your ancestor? Did the Union James Capp come from the same county as your ancestor?