I have an older, I do mean real old GS4.  It is NIB.  I am installing DCC in all of the loco's I have.  I read some place, I could be wrong, but the newer tenders have power pick up and mine does not.  What would be an easy way to install the DCC with sound in this engine?  Order the tender and the circuit board for the engine and wire it up?  Just buy a steam sound decoder from Soundtraxx, MRC, Digitrax or the like?

Thanks.

Buzz.