[Milsurplus] Any reason to Navy ID numbers

[POWERMWT at aol.com]

I'm trying to understand the Navy's terminology during the W.W.II period. 

So, for CVD-10182, the C is for Contractor, the VD for Willys-Overland and 
10182 is the model number? 

I'm also assuming the Navy had these numbers for other items besides radio 
systems, so does the C mean Contractor for a radio system? 

Regards,
Mark Tombleson