I stumbled across an interesting article from Ford Vehicle Capsule Reviews:
Ford sunk millions into the new manufacturing plant for the 1999 Super Duty F-350 DRW. For 1999, Ford hasn't changed the Super Duty F-350 DRW much, though it did expand the availability of the higher-end trim. In hopes of putting the Super Duty F-350 DRW

Found at: Ford Vehicle Capsule Reviews