Here is the reply from the Vicksburg National Military Park.
We are happy to assist you with your inquiry regarding "Who is Union Col. G. T. Tucker?". Although we do not have the reference in the Confederate Veteran, we do have The Vicksburg National Cemetery: Vicksburg National Military Park, An Administrative History by Richard Meyers. In it he references Lt. Col. Gilbert L. Parker, Assistant Quartermaster at Vicksburg . His source is Record Group 92, Office of the Quartermaster General, Cemeterial Files, National and Post Cemeteries, General Correspondence, Vicksburg, National Archives. We hope you find this information useful and if we can be of further assistance, please contact us.
Now to figure out if he is the Union soldier I seek, mentioned in previous post of this thread, and when he was in Vicksburg to collect dead.
Thanks for any input.