Scott,
 
Track down the Bureau of Land Management in California, as they have worked  
on Patton's desert training camps. I think California State Parks has done  
something too. It is possible that the Army at Fort Irwin has done something.  
You should check with the BLM.
 
There is a large collection of 1902-1922 U.S. Army material recovered from  
CA-SDI-12000 at Fort Rosecrans, San Diego, California, but it is not yet  
analyzed for publication. 
 
Roger Kelly has worked up some material from the Presidio at San Francisco,  
although I have not seen what he did.
 
Ron May