Pictures? It sounds to me like someone put a pair of what started out as "accessory horns" and later became "town and country" horns on the truck. I doubt the truck came from the factory with them installed but they could have been installed by the dealer, the owner when new or anyone since.
Do they look like these? These are accessory horns that were dealer installed on my '38 coupe. They are MIGHTY loud for 6v horns.
