George Plimpton is familiar to American viewers for his have-ago-at-anything approach. He has chanced his arm on the flying trapeze at the circus; in Las Vegas he has tried his luck as a stand-up comic, and in Africa he has stalked the world's largest elephant. This week he enters the Mexican 1,000-in a dune-buggy. In preparation for this gruelling race he consults Jackie Stewart and helps him in the pits at the Monza Grand Prix.