So, okay, Jim drives a Pontiac and Rocky has his GMC pickup. Has anyone elso noticed that most of the vehicles, especially the prominent ones, are General Motors cars and trucks? Was GM a sponsor of the series? Fords and Mopars do show up, but mostly as cop cars and in stock footage. Hey Harvey, there's that silver Vega at 4:02 behind the bus before the Eldorado. It will show up in every episode throughout the first season.
On another note, isn't it strange that the man sitting in the back seat of the bus (a GMC)looks just like Noah Beery? (3:29) Most notably in the wardrobe he is wearing in these shots, note the hat. He is kept "in shadow" so that the focus stays on the guest star. But looking at him there and also as he gets off the bus at the beach (the guy with the fishing gear, interesting) he passes so quickly that the eye picks him up as Rocky. Of course the actor playing Rocky in this pilot episode (Robert Donley) is nothing like our beloved Pidge. (Noah Beery's nickname, look it up on Wikipedia or IMDB)