Picking up where his grandfather left off, Bob Thomas took the reins of what is now Bob Thomas Chevrolet-Cadillac-Honda in the 1970s and built it into a business that topped $36 million last year. On average, he has about 300 cars on his lot. A graduate of Stanford University, where he majored in history, Thomas has steered the dealership through roller coaster economic times, which tug mightily at the car industry more so than others.