I suspect this is his grandfather:

Edward Stacy, Private, Company F, 36th Regiment, Alabama Infantry, captured at Spanish Fort, Alabama April 8, 1865, received at Ship Island, Miss. April 10, 1865, transferred to Vicksburg, Miss. May 1, 1865

NARA M311. Compiled service records of Confederate soldiers from Alabama units, labeled with each soldier's name, rank, and unit, with links to revealing documents about each soldier. Roll: 0367