An N scale 4-4-0 outing
I took my Model Power 4-4-0 and my Atlas 4-4-0 up to P.A.N.T. to compare and contrast these two models. Here's the Atlas model next to a photo of SP&S 50, which was formerly UP 623. This doesn't seem like a difficult conversion at all, and converting the model's tender by adding an oil bunker would provide space for a TCS Z2 decoder.