Didn’t the Santa Fe railroad remove the steam generator units from the top rear of the FP45’s and weld a plate over the holes when they were modified to the Superfleet paint configuration? The new Athearn “N” scale Santa Fe FP45 Locomotive in Superfleet paint still has those steam generator pipes in the top back panel. The model with dcc and sound runs and sounds great. I have four of them running in a consist and would recomend the engine. The speed range runs from a creep to fast road speed and are more than able to pull a 40 car train.
I found an artical on Wikipedia Free Dictionary under EMD FP45. The steam generators were removed when they were converted to freight service with blue and yellow paint.