Here's a link to the page for '44-'45-'46 Chevy trucks, from the April 1, 1948
Red Book. By then, OPA restrictions had been lifted.
These books were used by dealers, insurors and law enforcement to determine values and authenticity of used vehicles. I have them going back to 1926, and over the years have used them, among other things, to verify Serial/Motor numbers in several antique car collections and to correct the Buick Club's Judging Manual. Since they were contemporary accounts of industry data, I trust them implicitly.
http://photos.aaca.org/data/509/44_5_6_Chev_Truck.jpgThey came in very handy as evidence to convince our DMV of the legitimacy of my Bookmobile, which as a state-owned vehicle had never been titled till I acquired it.
I think this pretty much corroborates Jay's source material, as well.
Old's serial number holds the key to his truck's provenance.
TG