I find this ad from the June 22, 1964, issue of the Staunton Leader out of Staunton, Virginia, a good early example of a begining move from the jeep as a utility vehicle to it as a vehicle for outdoor recreation. Though the ad still focuses on the jeep as a way to get to these fun endeavors, it wasn’t too much longer before an inflection point where the jeep-journey itself was advertised as fun.
Remember that by 1964, Four Wheeler Magazine had been out for two years, a publication that helped spread the message and the hobby of four wheeling pursuits (clubs, jeeping, modifications, and racing).