The decimated Phillips Georgia Legion and the Seventeenth Mississippi led the two columns of Rebel infantry that attacked Fort Sanders. The arrangement, with the PGL at the head of the left column and the 17th leading the right one, was a bit unusual.
The Legion, part of Wofford’s Brigade, was more accustomed to coming up in line-abreast behind the Mississippians, as they had at Gettysburg. The most complete book on the Legion thus far seems to be Coffman and Graham’s 2007 history “To Honor These Men.” The sales page doesn’t have Amazon’s Look Inside feature, but Google offers limited searches of the text here.
Alas, there is no book on the Seventeenth as of yet. But there is my digital regimental on the 13th Mississippi (so far up to February, 1863, in its historical chronology), which came in right behind them in the attack.