St. Regis is putting guests behind the wheel of a brand-new Bentley to take on the twists and turns of California’s Pacific Coast Highway. With the Pacific Grand Tourpackage (from $6,900), guests of the St. Regis San Francisco and the St. Regis Monarch Beach in Dana Point get their pick of a 2013 Bentley GT, a Bentley GTC, or a Bentley Mulsanne for the 500-mile-plus drive between the two hotels. Those who purchase the package begin with a two-night stay in a suite at either of the hotels. After enjoying panora…