First Small Truck With Air Conditioning in United States

I am considering buying an antique truck for deliveries...a small
enough model that what would hold less than today's minivans. What's
the first year, make and model offered in America that had air
conditioning as an option?

I understand some cars, like Franklins, as early at the 1910s, had
ammonia-based air conditioners. Although Franklin was a fancy car,
some truck must have had it available.