Mantua All Right
Need a little auto focus? The first picture will do nicely.
Ok next. I do not see corrosion. The shell got the worst. Now, that white gear, you see is the main drive from the motor. All those rods actually supply power to the other three axles. A dremel with a wire brush will clean them up.Now the first picture, just outside the left frame is the two screws holding the cab. TO the right under the small front wheel axle is the screw that holds the shell. Remove those and the shell will come off. Then we can see the motor.
Now for electrical theory. You have two rails. The wheels to the loco are insulated from the track except to one side. ANy axles removed have to go in the same way. The tender is the same but the trucks pickup the charge from the other side of the track. Then the wire goes to the motor and ground out through the frame.So the tender trucks need to be pointing correctly. If not you get a shortbecause you are connecting both sides of the track. Can you look at the train and see which side is used by the tender and the loco?
I modified your picture. I couldn't access your photobucket so I copied it and uploaded to my photobucket.
This is the tool to remove the rod nut.
I would like to know how much train stuff can a SAHM do!! Keep it up!