Huge site with pictures and lists of just about everything, or at least way more than I'll ever know, in terms of various crates and boxes used by the Germans in WWII. It's in French but you can translate that with Google and it has measurements! So if you ever wanted to add some boxes to one of your pieces, or identify one already made by 21st Century or someone, this is the place.
http://wehrmachts.kisten.free.fr/