Doug
I believe that your GG Grandfathers pension records are some of those that put me on to that reference to the early history of Hardy's Regiment. It has been like trying to solve a 150 year old murder mystery. The clues had all been scattered and were few and far between.
The role of Portlock's regiment during the Arkansas Post-White River Union exposition of January 1863, particularly at St. Charles, had been completely over looked. Only half of that Regiment when to Arkansas Post to be surrendered there. the other half remained at St. Charles to dismantle two 8" Columbian Guns, from the CSS Ponchartrain, at St Charles and move them to De Val's Bluff where they were captured being readied on railroad flatcars to be shipped to Little Rock.
There is a lot of Arkansas History of this period that has yet to be correctly written about in the general public.