What you can't see in these photos is if you sat in the car, the radio, glove compartment, cup holders, etc were all still in tact so the actors had as realistic a space to play as possible.
Behind the car was a giant wall of maps. I found old atlases and cut out the maps, then connected them so they would drape over the other show's set like a curtain, and create a backdrop that would allow the car to be the focus, but add an extra layer of meaning and nuance to the set.