You also might want to consider the set of plates for the M1907-08 uniforms from Major Arthur Schmidt, "Die grauen Felduniformen der Deutschen Armee" 1912. This was reprinted in 1983/1984 by Druckerei Nehlsen, Hamburg, ISBN 3-922565-13-1. It shows all the branches of the army in color with the uniforms and insignia of the enlisted ranks. Though similar plates are in Kraus, these expand the information. I always go to this first for a quick reference on these uniforms.
Chip