Thanks to everyone that responded. I was finally able to get into both tenders. Here is what I have found for everyone's general information. The Spectrum long tender has pins to accept a 6 or 8 pin decoder. Also, the board sits low enough that the contacts from the trucks rub onto brass springs mounted to the board. The 2-4-0 tender's decoder is hardwired and the trucks contact brass springs attached to the floor of the tender and wired to the board. Not going to be an easy swap as I had hoped. While I'm no stranger to electronics, I am somewhat of a novice when it comes to decoder installation. I'm a bit confused about plugging a decoder into the pins. I thought the decoder usually had the pins, and it attached to the loco. How are the wires to the motor attached? Anyone willing to PM me at this screen name on the yahoo network and offer their expertise?

Thanks again.

i, too, would like to upgrade a Bachmann loco to a different tender. Here's my scenario. I have  one 0-6-0 from the Durango & Silverton set,  one decoder equipped 4-6-0, and one Spectrum long tender. I'd like to put the long tender onto the 4-6-0, presumably swapping the decoder over to the new tender, then put the tender from the 4-6-0 onto the 0-6-0 and convert it to DCC. However, I cannot figure out how to get inside either of the tenders! I feel like an idiot. But I don't want to break them. Can anyone point to a YouTube video that describes how to take them apart? I'd really appreciate the help.

Bachmann, please continue to improve your locos, and don't stop putting decoders into them... despite what other's are doing.