This history covers the 5 regiments which made up the brigade known
first as Gregg's then as McGowan's brigade.
The 1st SC Volunteer Infantry - Greggs
The Twelfth Volunteer Infantry
The Thirteenth Volunteer Infantry
The Fourteenth Volunteer Infantry
Orr's Regiment of Rifles
This is an excellent blow-by-blow account of the actions of this brigade, but it contains no rosters and losses of officers only listed by name.
Col. Rivers was commissioned by the State of SC in 1862 to begin compiling a Roll of the Dead. He began that work during the war based on newspaper accounts, letters from survivors and personal knowledge of the battles. After the war he continued compiling this Roll even though the state never paid any of his expenses. Compilation continued up until his death about 1890. After his death, the state paid a couple of ladies to compile and transcribe Col. Rivers' notes and this transcription is the basis of the book. The book was made from originals of the transcriptions. The work was stopped and restarted at least twice because of apparent errors, but at this point it's all we really have to work from. Broken Fortunes - the new book from the State Historical Society corrects and corroborates some of River's notes. As far as I know the original notes have been lost.