2) determine what "k.d.x expo" indicates. It seems to be an export, but not to Canada, Mexico, or Europe. Maybe Japan?
1935 Chrysler Airstream Series C-6 KDX Sedan (sold or no longer on the market) - PreWarCar
... talks about a 1935 Chrysler Airstream with a KDX designation, and mentions Italy and South America.
I also found a discussion, on aaca.org (Antique Automobile Club of America),
about an owner from New Zealand with a 1939 Dodge D12 sedan that that has KDX written on the part number for the seats.
Someone else there mentions that export models (at least for that car) were classified as either CKD
(Completely Knocked Down) or KDX... but did not know what KDX stood for.
* By deductive reasoning, my guess is that it stands for "Knocked Down Export".
Searching for "Knocked Down Export", I found this:
Complete knock down (CKD), is a complete kit needed to assemble a vehicle. It is a common practice among automakers, as well as bus and rail vehicle manufacturers, to sell knocked down kits to their foreign affiliates in order to avoid high import taxes and/or receive tax preferences for providing local employment.
An incomplete kit is known as SKD or Semi Knocked Down. Both types of KDs are collectively referred to within the auto industry as KDX or "Knocked-down export" , while cars assembled in the country of origin and exported whole to the destination market are known as BUX, or Built-Up Export.
I'm now thinking kdx parts are in fact the same, but in various stages of completeness.