I fitted the smoke unit used in Lionel's first Legacy ten wheeler in my Harriman 2-8-0. EOB provides the chuff trigger. I used a reed relay (not to be confused with a reed switch) to provide the isolation between the fan motor and chuff input on the R2LC.
Mine is lettered for NYC and will get de-Harrimanized and modified to make it a little closer to NYC prototype.
Piston:
Fan:
Bracket:
Pete