Hmm. I'll model it in Trainz for you. I just need the to have the specifications of the model, excluding the wheels, Then I'll resize it to the size of the JointedRail Flatcars.
I am doing a re-skin of majekear's skybox without all of the company logos on the sides. It going to be a MTTX flat, the lack of clear pictures of the ends have got me stumped for the moment.
This is what I got so far