Updated 4-stud-wide GP15T, GP38, and TTX intermodal railcar

My updated 4-stud-wide GP15T, GP38, and TTX intermodal railcar. I designed my 4-stud-wide rolling stock with the ability to run on proper 4-wide-track in mind (theoretically, the bogies can rotate, but these MOCS are entirely virtual for now) and to keep proportions as accurate as possible (the locomotives are a bit too tall, but I think they look sufficiently in-scale), but with the previous plow design with two 1x1 brackets, you could barely couple two locomotives together, and there was...