I am in the process of drawing scale CAD drawings of the X-3 tank car. I would like to do the 6500, 8000, and 10,000 gallon versions. I have been using the 1922 CBC as a source as well as the photos on Ted Culotta's web site and the frame drawn in the CBC is different from the photos I have as well as the Sunshine UTLX X-3 kit. The CBC frame is not square but slants from the coupler pocket at a shallow angle. The Sunshine kit has a square end. Which was more common and is there any other reference material to help me produce accurate drawings? Thanks