This is a model of the Pennsylvania Railroad's Test Weight Car #490398. Here is a description of the car from the Railroad Museum of Pennsylvania, it's current home:
"The Pennsylvania Railroad built the Railroad Museum of Pennsylvania’s short and dense test weight car No. 490398 car in its Altoona Shops in 1891. It was designed to calibrate scales at 30,000 pounds on inspection tours, which would last anywhere from six to eight weeks. The railroad hauled scale test cars, accompanied by a scale inspector, at the rear of the train just ahead of the caboose, and usually in different sized pairs that would allow an inspector to calibrate scales at two different weights. The American Railway Association, predecessor to the Association of American Railroads, required that railroad freight scales be tested every six months to ensure accuracy. No. 490398 operated into the 1980s, where it was the oldest car remaining on Conrail’s active equipment roster."
I made sure to get the stickers just right on the sides of the car. The only one I left out is one that hangs from the handrail and reads, "Do not make repairs to this car unless directed by scale inspector." I left this one out because I couldn't figure out how to attach it properly, and the text size wouldn't be legible that small anyways.
It's a rather simple MOC, the only SNOT part is the railing because upside-down is the only way it would fit.
The couplers are 1 plate higher than standard LEGO trains, because I didn't want to use LEGO buffers and if I put them anywhere else they stuck out too far.
Quoting Trevor Young
Nice. And the coupler issue, Why not use the normal 9V ones and put it upside-down?
You know I had considered that but in the pictures I was referencing there was some mechanism (couldn't positively identify it) hanging down from the coupler. I just tried what you suggested though and it really does look a lot better. Thanks for the suggestion!