Not sure when the formal Euro Delivery program began but I picked up a 220SE Sedan from the factory in 1963 just before returning to the US from Army service.
Now that you've jogged my memory, here's the story:
The car was Tobacco Brown, the same color as my Pagoda.
GI's used American Express for banking. German nationals could not use an AMEXCO check so I paid for the car with a bag full of US cash. The dealer sat and counted US$4,000 in 20 dollar bills.
(Some car orders were written in dollars, some in Deutsche Marks. When the Mark was revalued upward in the early '60, cars with Mark contracts increased 20% in cost because of the new dollar exchange rate. Mine was a Dollar contract so there was no affect.)
Diplomats and US GI's were given deep discounts in those days. I paid $4,000 for the car which was selling for over $7,000 in the US.
I went to the Sindelfingen factory by bus and taxi. Receptionist made a call and soon a tall, elagant looking Customer Rep came out in a long white shop coat. He guided me on a tour of the factory which I have never forgotten.
Absolutely clean and neat, several long assembly lines with cars in various stages of build were moving slowly along (perhaps your W113 was in my view?) A car would arrive at one spot and on a ceiling track above was the engine for that car. The track became lower and carried the engine right into the engine compartment where it was installed in just a few minutes. I was amazed that the correct engine and car would arrive at the exact same moment.
A few minutes later, the seats were installed, battery, engine "juices" installed, etc. Just minutes after the engine was dropped in, a technician jumped into the newly assembled car, started the engine and drove the car off the line. Wow!
Then my guide showed me through a swinging door into a small rotunda lit by a single ceiling flood light. Displayed in the light in all its glory was my 220 SE, a thrilling sight.
The only non-fun part was crawling along the Autobahn at 40 miles an hour for the Break-In period...but Mercedes had put a "Breaking In" sign in English and German in the rear window so the Porsches flying by would know why you were crawling along in the right lane.
Thanks for the memory.
Richard M