Have you seen "The Iowa Department of the Grand Army of the Republic," compiled by Jacob A. Swisher? It was published in 1936 by The State Historical Society of Iowa. It includes a discussion of the early difficulties of establishing/maintaining the Iowa Department. It then goes on to include a full-page picture of each Department Commander and a one-page summary of his life and war record; starting with James C. Parrott and continuing through Jonathan C. Hanes.
I have a copy - let me know if there is anyone you are looking for.