Here is a "project piece" example of one of the Marx 6 inch tin lithographed Army Supply Train Official Car observation car with lighted drumhead.  The car has 4 stamped metal wheels on metal axles, and tab and slot type coupler on the front.  Unfortunately, the car has serious llithography loss and damage throughout, and is missing the center rail pickup and the cover over the rear light.  Perhaps you need the base to a lighted Army Observation, or the rear railing, or maybe just a starting point for that unique custom car you've been thinking about doing!  I am sure this will be of use to someone out there, and the Marx 6 inch Army Trains always seem to be a high demand item.  Photos show the car from all 6 sides, with a yardstick in the shots for size reference.  Priced to sell, with only actual USPS Ground Advantage or Priority Mail cost charged to the winner!