Some if not all of the modifications to the Futura concept car that became the original Batmobile were done in metal by Bill Cushenbery.
http://en.wikipedia.org/wiki/Batmobile
"Barris hired Bill Cushenbery to do the metal modifications to the car and its conversion into the Batmobile was completed in just three weeks."
More here:
http://auto.howstuffworks.com/1955-lincoln-futura8.htm
They did later us the original to make fiberglass molds to make several fiberglass replicas, but the origianal #1 car is metal.