Mice really dislike mothballs....they also like to nest in the exhaust pipes. I have a 1968 Olds 442 that I bought new, drag raced for a couple of years and then parked it in Mom's garage for four years while I was off at college. I put mothballs in the interior, trunk, engine compartment and stuffed the exhaust trumpets with steel wool and refreshed the mothballs when home on holidays. When I returned to pickup my car not a sign of mouse damage! The mothball smell took a while to get gone though.
I still have this car today with only 13,800 miles on it! I only drive it occaisionally and now use a high frequency plug in device that chases those rodents and bugs.
I would recommend this electronic device which can be found at Home Depot or Lowes or Radio Shack.
Hope this helps. :thumbs