Hello Jon,
From my GPW studies and databases, I believe your GPW 108104 should have come from the Louisville, Ky. assembly plant . The most likely DoD should be mid April, '43.
The good news is that Jim Gilmore has a copy of the Ford shipping records of the Louisville plant in the spring of '43. These records show how the GPW was shipped, when it was shipped, the original hood number, and the type tires used (not the brand used ). These records do not give the DoD of the GPW but the DoD has to be before the shipping date.








