Do not forget the coal ramp, 456. Years ago my son and I put together an operation using the 397, 456 and 497. I do not remember exactly how it worked, but the idea is that some of the accessories will load or unload the side dump car and some will load and unload the hopper car. You can set things up so you load the hopper then unload it and reload the side dump car and unload it so the hopper can be reloaded. We did not include the 97 in our operation. There was coal everywhere. I think a 623 did most of the work. Uncoupling tracks were located where needed and a spare cut of cars is required to use the coal ramp. We had a lot of fun.