When I lived in the Los Angeles area I saw quite a few commercials he did for Cerritos Auto Square (a group of dealerships owned by different people who advertised together as a "destination" for car shoppers).

Here's a link to my favorite. Great line in it: "Don't worry about the salesmen. Anyone can whup a salesman..." https://youtu.be/P1UE4_B_6xY

Edit: lots of his commercials are on YouTube.

Edit 2: Jim was very good as Jed Clampett in the Beverly Hillbillies movie, too. The first half of the movie was hilarious.