Mark, Triple Header! How cool is that? Actually I didn't see this at first I was busy looking at your scenery. Which brings me to. Just being a nosey neighbor. How much of this is your actual work and how much of this is photo shop? One of the advantages of photo shop is you can get ideas for finishing off your scenery. I'm impressed.
Here is the original photo. http://www.trainboard.com/railimages/showphoto.php/photo/132843 Mostly I just use Photoshop for composition and color correction as well as cleaning up/replacing the background. Sometimes I also need to pull the color, or make a part lighter/darker to make things pop, but as far as the model work, that all remains original.