Haven't read it, but Steve French has a new book on McNiell's command, "Phantoms of the South Fork." (2023).
From some old publications:
Capt. John H. McNeill.
After John H. McNeill's death, his son Jesse C. assumed command of the rangers.
Tip O'Ferrall, of the Confederate cavalry, later a Governor of Virginia, noted of Jesse McNeill's command of the rangers in 1865.