Hi Marc,
Did you check civilwararchieves.com? That would give you a tumbnail sketch of that unit. I understand that the history of the war of the rebellion is now online but don't quote me. There is a very interesting book " A History of Southern Missouri and Southern Arkansaa' by William Monk who was a town constable who rose to if I am not mistaken to a Col in the 11th MSM. On page 81 he go's in detail about the 6th Mo fighting the Battle of Mammouth Springs in Ark Mar 10 1862 where they inflicted heavy loss on the Bushwackers. From what I gather Union and CSA troops both spent a lot of time in Ark and Ark troops both CSA and Union spent a lot of time in MO. I hope thisa helps.
Leonard Unger