Pat,
I did it for a friend and have given it back to him. It was a MTH CNJ model.
I put the CC in the front of the tender with RS board double sided taped onto R4LC and a razor thin speaker on the slotted circle. By using the reed switch, it snugged in and surprisingly had no rubbing issues. I did have to redo the engine 10 pin harness, there was a funky 14 gauge wire added on the blue engine power wire that would not tuck in anywhere.