Early, before 1992????, Atlas SW's, had Dallee Drive systems, and a poor sound system. The speaker was mounted, front hood area, under the Engine, heat exhaust port. Model history, early Train America Studios, Generic, TMCC conversions, were done to some of these models, Youngstown Ohio. IMO, I have one, of the Dallee powered SW's, that I converted to TMCC, myself. A Difficult and time consuming project. At the time, speaker, and TMCC parts were available from Atlas. Key was an interesting TMCC mother board, that had a, (bottle shape), to fit the die cast hood. TMCC antenna was installed, in the plastic cab area. Over time, there were two different antenna locations. The size of the antenna, second modification, was larger, and positioned top of the cab. Second antenna location improved TMCC operation. These models also had forward/reverse operational head lights, and electro-couplers that were functional from the hand held remote. If you have the TMCC instruction guide, that came with the command base, and handheld remote, these engines, once assigned an Engine Number, could be programmed as a "Lash-up", Multiple engine consist. Some of these early instructions should be available Lionel website archives. Or in the archives of this web page. Have fun, Mike CT.