Faneuil Hall Marketplace, the historic shopping and dining area located in the heart of Boston, will be the venue for British Car Days, a series of four summer weekend shows organized by the Boston Area MG Club. The series begins with a display of Triumphs on June 19, and continues the following day with a gathering of Rovers. Three more shows are scheduled for July 17, August 21, and September 25-26, the last of which includes a people