It looks like your only course will be to [re]read the novels and make your own notes. But - based on my vague memories of them - I think you'll probably just have to make up something. As I remember it, Dickson's writing focused on command philosopy, rather than practical details of process. I've heard "Dorsai!" described as a treatise on scifi commanders, as opposed to how "Starship Troopers" is a treatis on scifi enlisted men.

Since (again as I recall) the Dorsai books didn't feature anything that was very high-tech in the way of equipment, I would just appropriate the organizational notes of something like . . . asy . . . the CoDominium Marines from Pournelle's Future History stories. Since the CoDo Marines were descended from the French Foriegn Legion, its organization (which would likely be the same as those of other French Army units) should be easy enough to discover.