Good stuff guys!  I have played a bit with the wiring harness as directed.  Seems to do the trick.  Engine even runs backwards now without pushing the tender off the track.  Thanks for all the great suggestions!

Just got a new 4-6-0 with 63 drivers.  Awesome!  Having a little trouble keeping the front wheels of the tender down and on the track.  Seems like the wires between the tender and engine are pushing the coupling aside and lifting the tender.  Any secret to how to hook up the engine and tender?  Right now I have the coupling between the two sets of wires.   Many thanks!