In the later episodes of The Beverly Hillbilly's, I have seen a red '70 or '71 Challenger convertible show up either Mr. Drysdale or Ms.Hathaway drove.
I remember that one too, the Challenger, Coronet and a '64-'65 Fury Convertible stick out really well in my memory. I'm sure she drove other things, not sure if Chysler lent them new cars every model year though.