 162B and 163B returned to their previous identities of 6T and 19T respectively, but 165B, 168B, 171B and 169B became T cars 20, 21, 24, and 26, ignoring their previous identities of 21, 43, 101, and 39T.In 1958 class designation on the Melbourne suburban system was abolished altogether, meaning that the fourteen BT trailers were no longer any different from the rest of the fleet, all cars receiving upholsters seating as the new standard.However, those cars kept their BT code, and they were joined by seventeen other vehicles to make a total 31 BT trailers.