I was referring to the Baldwin DT-6-6-2000. SP did have a bunch of the SW-9 and TR-6 A and B (I would take an accurate TR-6B unit)
My most sought after that I'd like to see in Ready to Run N scale is the H20-44, preferably in P&WV paint. One of my favorites thanks to Bachmann and Great Decals is my H16-44.