https://www.metv.com/stories/when-the-beverly-hillbillies-was-turned-into-a-movie-buddy-ebsen-welcomed-the-new-jed-clampett

The series was developed into a movie that premiered in 1993.

The article says Ebsen and Varney were the only two to play Jed Clampett. Hank Kimball also played Jed Clampett in the Green Acres Hooterville stage play version of The Beverly Hillbillies. I bet Jed has been played by a few other actors in parodies over the years.