This UP GP40M-2 started life as a GP40, first working on the B&O in Feb of 1971 as B&O #3762. It eventually wore CSXT 6538, and was then retired by CSX, rebuilt, and sold to Southern Pacific in June of 1991 as SP 7122. It now sits at Dupo, IL on 11-3-2006 as UP 1500. This unit may easily have seen almost all of the 48 contiguous states in its 35 year career, probably many times over.