ACWR recently completed their first slug set, 703/704. This is a similar team to a CSX ROAD MATE set. They are apparently quite pleased with the performance of this duo, and I believe may plan on doing another. I don't know if this is a candidate for the next one, or a parts source. Slugs can be used for salvaging traction motors or a few other components. BTW, here is a link of it in retired state at UP, close to what your photo is, so this will hang around for reference:
http://www.rrpicturearchives.net/sho...spx?id=2208056
They definitely removed something from the end. I was suspecting remote control gear, but it appears there was something else there on the end that was cut away. Possibly was a sand box, based on the access port on top.