I think I fixed it. I removed the two screws that hold the microswitch and then the 4 screws that hold the entire mechanism to the bottom plate. You can then turn the plastic mechanism upside down and remove two more screws that hold the circuit board. Then I unplug the 3 prong plug that is at the other end of the microswitch. I cut and then removed about 1/8 in of red wire and resoldered the red wire at the microswitch since I discovered that moving that wire would start/stop the action so I think there might have been a break in it. I should have taken a picture of that switch out of the car. After putting it back together I got it to work reliably but it is very sensitive to exact position on the operating track.
There are 4 screws that hold the shell to the frame, 4 screws that hold the bottom door guides on, 4 screws that hold the mechanism to the frame and 6 screws that hold the top plate to the mechanism but you generally do not have to remove those six screws I discovered.
I realized there does not seem to be much interest in this thread but this operating car is really rather neat, with two figures 'working' inside the car, interior light and operating smoke unit and the discharge of the dry ice boxes. It is one of the few operating cars in the Premier line by MTH, so it is also scale.
I also noticed that the mounting posts are starting to split and I thought I was careful.
I cut and resoldered the red wire after removing the switch from the car and checking continuity.
Putting smoke fluid in the car is tricky. The smoke tube is to the right of the worker, the shiny part to the right of his head is the top of the tube.
