Update: Thank you for all the suggestions. I was able to slide the chassis out by using a small wooden block to push against the sharp metal chassis, while very slightly pushing outward against the aluminum shell. Once it started to move, it came out easily.
While open, I painted the white molded plastic with the seats and floor, installed more passengers, and changed the lighting to LED strips using the GRJ designed lighting board kits available through Rod Stewart, a forum member.
These cars have 2 Red maker lights on each end making a total of four combined in each car. I replaced each red tinted incadecent bulb with a Red LED. All four on each car were then wired in series along with a 500 ohm resistor and connected to the LED Strip lighting .
I was unable to obtain small rounded LEDs as small as the original bulbs. I was able to use 2mm red tower LEDs that fit and extended into the cars marker light openings. I painted the base of the LEDs in the cars interior with black paint so they wouldn’t show through the windows when lit. (Below is a picture of an original incadecent bulb alongside a 2mm tower LED.)
Ron