Dan,

I did read the articles at the link_s that I posted above, and I have read the information in 6 different 47-55 Truck Data Books.

The quoted information in my earlier link came from a Truck Data Book (I hold them in higher regard than the history-articles). Advance-Design trucks (and maybe earlier trucks) were painted at the factory with "high-luster Dulux synthetic enamel which is baked on in thermostatically controlled ovens." Air-drying Duco lacquer was available for repairs [this is also stated in Truck Data Books and on Dupont paint sheets].

For example: 1947 Chevrolet Truck Data Book