Look for routes by MSGSapper. He took the shortline routes by GFisher and updated them for TS12. I also have one on the DLS called Gloucester Terminal Electric. This is also based on GFisher's Gloucester Terminal Railroad. My version has a trolley service instead of being strictly diesel. You can always rip out trolley wires if you want. There's plenty of switching on this route if you're interested. I added in a yard and some big industries that need attention.
John