Original sentence: In 1974 the rear bumper was also redesigned.Powered by Lincoln's 460cid V8, the Mark was characterized by many standard power accessories and a richly appointed interior.The Ford Thunderbird was engineered on the same platform, and shared some of the Mark's styling and features, but for 1977 the Thunderbird was moved to a smaller platform.The Mark IV, offered only as a two-door hardtop coupe, was heavier than the standard Continental.The hallmark opera windows were added for 1972, and in 1973 the front bumper was redesigned for the federally mandated 5 mph (8 km/h) bumper.While the Mark IV carried over many design themes of the Mark III, such as the grille and spare-tire hump, it grew both longer and wider
Edited sentence: By 1975, it had swelled to an enormous size, and would only get larger for the time being.In 1973 the front bumper was replaced by a federally mandated 5 mph (8 km/h) bumper.In 1974 the rear bumper was replaced.Lincoln's "personal luxury coupe" grew enormous in its second incarnation, much larger than the attractive Mk III of 1968-71.Powered by Lincoln's 460cid V8, the Mark was characterized by.The Ford Thunderbird was engineered on the same platform, and shared some of the Mark's styling, but was its own car.The Mark, offered only as a two-door hardtop coupe, was also heavier than the standard Continental.The hallmark opera windows were added for 1972.The long hood looks like an airport runway from the driver's seat, even more so than the Continental.While the Mark IV used many design components of the Mark III such as the grille and spare-tire hump, it  was both longer and wider than the Mark III.While the Mark continued to grow in sales, the T-bird didn't, and for 1977, it was put on a smaller platform.a large number of standard power accessories, unique styling (with a distinctive faux-spare tire hump on the trunk), and an incredibly comfortable and rich interior