Hello, I'm new to the forum and dcc. I'm building a layout with my grandson. I have a new HO usra heavy mountain 4-8-2 SP  with oil tender, item 82502 Spectrum. Paperwork with loco says to replace dummy plug with decorder plug, can I plug a sound decorder in with a speaker so I don't have to rewire and solder? I've looked at soundtraxx decorders but don't see any I can just plug in and run.
Thanks,