I believe both William Z. Howard and perhaps a William H. Howard served. William Z. Howard was my great, great grandfather, 1836-1872, married to Elizabeth Welch, 1840-1867 or so, buried in Navarro Co., Texas, in Dresden.

Family lore says he was in Hood's brigade. The NPS Civil War Soldiers and Sailors system identifies these two as being in the Mosely's 7th Field Light Artillery, although I don't know much about that unit.