I don't see how you can even consider a 1959 or absurdly, a Mexican Beetle (hugely manufactured cars in highly organised production lines) in a debate between a 1938 and 1947 saloon.
The 1945-47 cars were often put together with whatever parts were available as large parts supply from manufacturers were still difficult until around 1948.
Excess prototypes parts such as seats, card cloth panels and carpets would seem reasonable to me, unlike body and mechanical items.
I can't see that it was so unlikely that whatever was available at Stuttgart would not have been put on a train to Wolfsburg.:wink:
I disagree, the prototype cars were hand built prototypes. There would be no reason to make excess items of anything, in fact there were differences between the different '38 parts. You can't get a bunch of door panels made up for doors that haven't been made yet and that may vary from any previous doors made.
And then to ship them 400 miles to Wolfsburg and to keep them through the war, is a bit of a long shot at best.
More likely is that made the door panels in '47 and copied the design from old photographs...
Also, the '38 and a '47 are as far apart as a '47 and a mexican Beetle. The only part I could see (after hours of looking) from a 'normal' split that would fit on the '38 was the bumper iron grommets.
Happiness is a stock VW