I agree with Pabakb. I registered my HMMWV in California with very little trouble. Albeit, 6 months ago. I installed a license plate bracket with lights, Brake and lamp inspection done by local state certified garage, VIN verification by CHP and I was done. Never ask about back up lights or anything. By the same token, when I tried to title my 5 ton 6 weeks ago. it took no less than 4 trips to the DMV before they referred me to CHP to verify that there was only one serial number on the truck. Apparently, there is a place for two numbers on the DMV form and going up through the ranks at DMV none of them---not even the "supervisor" could figure out what to do about there only being one serial number. They eventually sent me to the same CHP guy that verified my HMMWV and I was done in 15 minutes. It's just luck of the draw on who you get at DMV.
Id say don't get too frustrated. Just play dumb and try again at another office if you're getting questionable information.