I have read a quote regarding the FT's as such: So, it's safe to assume that they were on this service for a while, but what was their disposition after that, what did they do? They were repowered with EMD motors to become FA/B-1m's too - were there any external changes?
The MKT's EMD-repowered FAs ended up with bulging rooflines, and I'm sure the Rock Island's would've had them as well. Think about Christina - EMD prime movers and associated equipment were too large to fit in those Alco carbodies.
Some received Blomberg trucks and lost the grillwork around the headlight. Of course the main spotting feature would be the twin exhaust stacks on the roof. As with Rock Island practice there would be no dynamic brake detail on the roofs.