Hi all, I just found at s a DC Spectrum Western Maryland 2-8-0 #763 at an estate sale. It runs great but I would like to add a smoke unit. Is this possible? If so, which one(s) would work? I haven't opened it up yet to look. I don't want to tinker with it if I don't have to. The schematic leads me to think that it isn't, though. Any help would be greatly appreciated.

Thanks!