Since the 1st through the 6th U. S. Volunteers were made up Confederates who took the oath, can you look up the men in the records for these units. Although come to think of it, those records are probably here at the National Archives.

Lists of officers for these regiments are in the "Official Army Register of the Volunteer Forces, U. S. Army, Part VIII: Territories, Veteran Reserve Corps, U. S. Veteran Volunteers, U. S. Colored Troops," Adjutant General's Office, Washington, D. C., July 15, 1867.

If you can't locate a copy, contact me as I have a copy and will be happy to do lookups for you.

Alice J. Gayley
Pennsylvania in the Civil War
http://www.pa-roots.com/~pacw/