I was poking around on the web and decided to check out the Alaska Railroad web-site. While there I found a huge (15 Mb .pdf) “Load Manual” that describes how to secure various loads for shipment on the ARR.
From the home page - www.alaskarailroad.com - click on the '“Freight” link and the go to the “Load Manual” quick link on the left side of the page. If you don’t want to explore the entire site you can get right to the download link by going here: http://www.alaskarailroad.com/arrc294.html .
There are lots of illustrations and photos of all sorts of different and interesting loads and how to secure them to railcars. Perhaps some of this stuff will give you new ideas for your layout. Definately worth checking out!