Prototype - yard loading?

[blackettstreet]

I am building a small layout set in the 1970s-80s, the plan for which I have attached. The station at the top of the plan has a very basic, one-siding road served yard. I have read plenty about local yards in the steam era, but there seems to be little information about such yards in the BR diesel years. I want the yard to handle such traffic as coal, vans, steel, oil etc. So is there any way in which I can actually unload freight from open wagons on the model? Or am I just going to have to run closed vans and 'imagine' them being unloaded?

Help much appreciated

EDIT: By the way, I'm on a budget here, I'm not going to shell out £200 for an overhead crane!