One of the main goals of the federal clunkers program is to get gas guzzlers off the road forever, so the program requires them to be permanently disabled, a task handled by auto dealers. But that's just the beginning of the end and, really, the rebirth of the Ford Explorers, Jeep Cherokees and Dodge Caravans that consumers have been trading in for new Ford Focuses, Honda Civics and Toyota Corollas. Steel…