To clarify a bit, this movie was released in Oct of 1950, so that some of the actual race film footage, used in the movie, was from the 1950 race. The dark colored #17 car, that ran in the 1950 race, was the Wolfe Spl. driven by Joie Chitwood
Also some actual race footage, in the movie, was from the '49 race. The dark colored #17 car that ran in the 1949 race was the Balanger Spl. driven by Duane Carter.
The car used for all of the Hollywood movie scenes was the Don Lee Spl. painted as the "Brannan Spl.#17"