Thanks Jim for the detailed instructions.  I ended up taking to a hobby shop.  I'm supposed to hear back next week.  I hope it's just a simple fix.

Help!  I have a Bachmann Narrow Gauge Express (item 25002) steam engine that won't run.  I was given the set used but it looks brand new.  How do I take off the shell to check the wires.  I can see the tab in the back under the cab but I can't tell what's holding onto the front.  It's an On30 scale.
Thank you!