Tuscumbia Blues, aka Franklin Blues, was the nickname for Company E, 2nd Alabama Infantry, there is no Lt. Powers listed in the roster of officers for that company.
The only John Powers in the regiment was:
John Powers, Private, Company D, 2nd Regiment Alabama Infantry, enlisted March 26, 1861 at Ft. Morgan by Lt. Sharp for 12 months, deserted March 6, 1862 at Mobile, Ala.
M311: Compiled Service Records of Confederate Soldiers Who Served in Organizations from the State of Alabama
See also:
http://www.rootsweb.ancestry.com/~allauder/civilwar-franklinblues.htm