Bob,
Consolidations run great! as a rule.
The newer consolidations come with DCC on board. So it's simply a matter of pulling the plug on the old decoder and plugging in a DCC/Sound decoder, like a Tsunami.
Also, the newer versions already have a speaker mount in the tender. If memory serves, a 28mm (1") speaker fits.
You will probably have to solder an 8-prong plug to the decoder wires, and solder a speaker to the decoder output wires.
This should be a simple conversion, as conversions go...
Once in a great while, on eBay, one can still find "sound onboard" connies.
Call me biased, but you are starting off with the best all around HO steamer.
Regards,
Jonathan
Actually, as far as the wiring goes. If he goes with a Tsunami or Tsunami2 decoder, he can get a wiring harness that already has an 8 pin plug attached and cut the shrink tubing back on the decoder just enough to remove the stock wiring harness and plug the new one (with the 8 pin plug already attached) into place. All the installation instructions can be found on the Soundtraxx website under the Manuals tab at the top of their web page.