Below are two pics of the real thing. The first
is one of my pics of an HC-44, the second is John Whitmore's of an HC-41.
Jeff Hanke photo John Whitmore photo
The closest matching prototype is the Western Maryland HC-41 class. To make this class (WM #604950-604999) you would need to add a single strip of styrene across the car. See proto photo above for clarity. The rib runs the length of the car just above the words "Western Maryland". These cars come decorated already for WM, as seen below. It is a must buy. You can also decorate them yourselves. I did the 604999cs-wm car from an undecorated model. I use Herald King or Champ decals for these. Also note that this is one of the very few series of numbers that conflict with another Chessie road. There are covered hoppers from C&O and WM that look very similar that wear the numbers 604950-999.
The next closest match is the HC-44 class (B&O 605000-605499, C&O 604600-604999, C&O 605500-605899). The HC-44 is practically unique to Chessie, and only one other railroad ever purchased them. The problem is the tell tale sign of an HC-44 is the "birdcage" end. Look at the picture above left. Notice how the body of the top part of the car ends at the inside ladder post, while the WM car the body extends all the way to the outside ladder post. This "birdcage" is not on the Front Range kit and would require alot of work to fix. I just make mine straight out of the box and live with the flaw. These cars come decorated for the Chessie C&O cars, or you can decorate them yourselves. I use Herald King or Champ decals for mine.
Also, you will need to add weight to these cars. They are extremely light. I either add BBs held in place with white glue or lead weights.
Below are some pics of mine.