The revisions to the body were minor .
The most noticeable were a return to four - piece sliding windows to improve ventilation and to 203mm high route numbers at both the front and rear after the 127mm examples proved unpopular .
The revisions to the body were minor , and the most noticeable were a return to four - piece sliding windows to improve ventilation and to 203mm high route numbers at both the front and rear after the 127mm examples proved unpopular .