A great achievement of childhood is learning how to color inside the lines. In Little Rock, the new frontier for drivers is learning how to park inside them, specifically the trolley line. It`s the white guideline painted along the route the city`s new streetcar will begin running in November. Drivers are being warned that if they don`t get all of their car, including mirrors, inside the white line their car may get towed. If it extends across the line there`s a high probability it will block the trolley. There`s only 6 inches of space between the outside of the white line and the actual path of the streetcar - not a wide margin for error. The trolley`s next test run will be Thursday.