Are you aware of the tinplate billboards that Hallmark produced about 20 years ago? They had a line of tinplate pedal cars that they marketed. They also produced a number of signs and buildings in tinplate to go with the cars under the name Kiddie Car Corner. There were 3 double sided billboards that advertised other items in the collection.
This is the third billboard in the series.
Here is the billboard with several other items in the collection, some Hubley cars and an American Flyer Wide Gauge steamer.
I think that Steve Eastman uses these on his layout.
Northwoods Flyer
Greg