without marring the plastic?

Success!  I got the decoder installed.  It was a real shoehorn job.
Now a further question:  I have New Haven tenders because unlettered tenders were all sold out in stores and on line, including the Bachmann site.  How can I remove that lettering without marring the plastic?

I take it you're suggesting I could solder wires directly to the contacts that stick up through the floor of the tank.  How do I do that, in a space that's crammed full of other stuff, without unduly restricting the movement of the trucks?
Also, if I don't use the electronics board how large a resistor should I use with LED2? Or to restate the question a different way, what's the voltage rating of LED2?

Rivarossi 4-6-6-4

I have the tender now and have opened it up.  There is room for the Soundtraxx 750 decoder under the coal space, but in order to have room for the speaker I would have to remove part of the circuit board.  My plan is to remove the center, leaving both ends holding the contacts for the conductors from the contacts that ride on the axles and also the mount for the rear LED.  After all, my whole reason for changing to this tender is to get improved pick up from both rails through the tender.  But I don't know what the ramifications of removing the circuit board might be.  Ordinarily one would connect the grey and orange decoder wires directly to the motor brushes and connect the red and black wires directly to the pick ups from the track, so what does the circuit board do for me besides provide a resistor for the LED?  I got no documentation with the tender, which was purchased new as a separate item with no locomotive.

If I purchase an N scale Bachmann USRA 0-6-0 at my local hobby shop or on line ( new ) will it come with the new version of the tender that has all wheel pick-up or is that still a separate purchase I would have to make?

Is there room in the N scale Vanderbilt tender for a Tsunami 750 sound decoder and a mini oval speaker and enclosure?  If not, how about a 1/2 inch round speaker?