i have a 97 Bounder, built march 97 on a 96 chassis built in sept 96
the registration is 1997 model
the certificate of origin, is what counts when titling from new
BUT if the paper work has been lost or changed via auction or salvage and being bought used, then you are subject to what ever the local DMV puts on your new paper work, getting it changed after they put it in their system is pure H E LL
don't let them do that, question them every step of the way
and walk out and go some place else to another branch if there are problems getting it entered correctly