Indiana Harbor Belt IHB Slugs: PB3, 477, and 478. HO 1/87 and N 1/160. In HO, these are designed to fit an old Athearn SW7. I have no idea what to recommend doing for the trucks in N scale; so you'll have to figure that out yourself. Also included is a cab for kitbashing BU50. In HO scale, there are one-piece versions of the slugs and versions with separate frames/walkways and bodies. In N scale all the bodies are one-piece.
STL (Stereolithography, filesize: 4.6 MB)