You'd be surprised at the press something like this can generate, for both the show and yourself. Not to mention it puts old cars in a POSITIVE light, even to people who are generally anti-old-car.
Several years back, a local Little Theater group did a masterful production of "Driving Miss Daisy". Now, in the original stage play, Miss Daisy Werthan owned Oldsmobiles, not Cadillacs, and the producers wanted to stay true to the stage play. I was able to get 1948, 1954 and 1967 Oldsmobile Ninety Eight sedan owners to bring their cars as props. For the Saturday night performance, those owners drove the cast to the theater in the cars and dropped them at the front entrance in costume, complete with Hollywood style red carpet grand entrance.
My old HS English teacher played Miss Daisy, and when I opened the car door for her, her comment to me was "Leave it to you..."