N Scale Budd RDC-9 Body Shell. Shell is one piece and includes stepwells. Shell represents 30 cars built for the Boston & Maine. A few later went to the Canadian National. RDC9s had no end windows and body details different from other RDCs because they only had one engine. Shell can be made to fit N scale RDC drives from Kato and Con-Cor, though it is not designed specifically to fit either.