I'm not so sure that your ancestor is the A. J. Wilcox of the 10th Arkansas Infantry. The name is similar, but this man is carried on the rolls of Co. D, 10th Arkansas Infantry (although the Port Hudson surrender list shows him in Co. E), which was recruited in White County. There were no known northwest Arkansas men in this company. Before you consider this man to be more than a very tenuous possible connection, you might want to do some more research.