Lancaster and Chester #91 was the last SW900 built. It rolled off the assembly line in October, 1965 with sister unit #90. Fifty two years later, the end cab switcher is still on the L&C, though it has been relegated to shuffling cars at the Circle S Feed Mill for the better part of the last two decade while the railroad's other end cabs have been sold off. ancaster and Chester #91 was the last SW900 built. It rolled off the assembly line in October 1965 with sister unit #90. Fifty-two years later, the end cab switcher is still on the L&C, though it has been relegated to shuffling cars at the Circle S Feed Mill for the better part of the last two decade while the railroad's other end cabs have been sold off.