I'm interpreting the use of the word "vehicle" to exclude starships and other space-going craft. Thus, it was my understanding that the OP was asking specifically about the rules presented in the civilian and military vehicle books, not High Guard.
So to clarify what I'm saying – you can design ships for publication using High Guard and the core book, but at this time you cannot design vehicles - ground/grav/air/hover/water, etc. - using the vehicle design systems found in the military and civilian vehicle books, for publication.