Convertibles were rare even in the 50s. Chevrolet's Corvette didn't reach sales of 10,000 until the Kennedy administration.
George Lucas released the film in 1973. It was nominated for many Oscars, including Best Picture. As a kid he told his Dad he wanted to be a millionaire by age 30, actually not an uncommon aspiration for a teenage boy in the 50s, considering the degree of overall prosperity of that era, blacks and Hispanics excluded, of course. Lucas netted his million from the film, which had a budget of a mere $770,000. I think he needed to get the movie of an evening in 1962 about recently graduated high school seniors out of system so he could move to make his first billion with Star Wars.
Disney bought Lucasfilm making Lucas a multibillionaire. He is the second largest shareholder of Walt Disney Company stock. The largest is the estate of Steve Jobs.
The Wolfman died of a heart attack in 1995 at aged 57.