I purchased a Bachmann N-scale 4-8-2 Light Mountain w/DCC/Sound last year, but have never been able to get it to run.  The sound activates, but the only movement is one "chug" in whichever direction I've chosen on my throttle.  Has anybody else had this same problem?

I recently purchased two Bachmann 4-6-0 DCC-equipped N-scale Baldwin steam locomotives (Item No. 51451) as additions to my Denver & Rio Grande Tincup Branch (circa 1905).  I am going to use Surroundtraxx for my sound generator, but need transponding Digitrax decoders to move the sound around (Digitrax is the only game in town).  I've been able to remove the body of the tender of the Bachmann loco but in going over the instructions, it isn't exactly clear how I can remove the E-Z Command decoder and replace it with a Digitrax DZ126.  The instructions say to "remove the DCC board from the main board by tools" by cutting along perforations in the main board.  What the instruction don't say is whether one can directly solder the DZ126 leads into the labeled holes in the main board.  Since they are empty and labeled the same as the leads within the loco, I'm assuming you can, but I'd rather not fry a decoder if that assumption is wrong.  Has anybody else tried this and, if so, how did you go about installing the replacement decoder?  The instruction sheet, by the way, shows how the wires should be connected by color code, further suggesting that the Digitrax wires can be soldered directly to the main board once the DCC portion of the board is removed.