You have told us this over and over. Yet, you are unable to provide any data that would support your claim. You mentioned the US Dept. of Commerce. It is the US Department of Transportation responsible for this. The law that lays down the requirements of the VIN do not mention US content. And the International Standards Institute makes the actual requirements.
I have asked you to provide evidence that the 1, 4 and 5 mean anything other than assembled in the US, but you failed. You have yet to provide any satisfactory explanation of why identical trucks manufactured on the same line with essentially the same parts, both with 90% North American Content, have different numbers. The explanation is that the numbers mean assembled in the US. There are three different numbers because the VIN applies to so many things that are made in the US: Buses, cars, trucks, SUVs, 4-wheelers, motorcycles, trailers, farm equipment, construction equipment. Because of all the stuff made in the US that carry the VIN, the US needed three different first digits.
Jeff