Ken,
A map on page 371 of Wiley Sword's "The Confederacy's Last Hurrah" shows the 23rd Corp (of which the 104st Ohio was a part) facing Cheatham's Corp @ Shy's Hill (Attack on the Confederate Left, 4:30pm, Dec. 16 - Nashville) Stewart's Corp (Sears' Brigade included) was on Cheatham's right flank. It appears from the arrows showing the union advance and Confederate retreat, the Union troops over-ran the entire Confederate line. It may be a bit of a stretch, but, the possibility exists that the Mobile Depot flag in NC may be from Sears' Brigade. It could just be wishful thinking on my part, as well. I'd love to find some more detailed tactical maps that show the Regimental alignments a little better.
CB