Discontinuity: when they start parking the yellow '65 Dart convertible, the car behind them is a blue '63 Valiant. Once they're in the space and start talking, the car behind them is something else, painted green, maybe a GM product.
I have another picture of a DartCharger that was used in the Lucy Show. Wonder if it could be the same car? Can't be that many DartChargers in the movie production!
Check out the wronmg gas cap. It's a chromeone and what I know of they were for export cars only!