I thought the wagon I bought recently off Ebay with the coal load would look nice a private owners one. I removed the side straps; after hunting on the web for a suitable image I used it to make two printed sides for the wagon - I used photo paper but printed on the reverse side to give a smooth surface to stick to the wagon.
I mixed some paint to match the sides and painted the other parts of the wagon; then I stuck the sides on with PVA. The side straps were stuck back on, then a few coats of spray acrylic varnish applied.This will go nicely with the coal office and man with sack of coal; I have a coal staithe on order - a nice line side feature to add to the garage layout.