I was lucky enough to be able to tour the Factory outside of Stuttgart back in 1977 and also the museum later in the year.
The engine testing facility while less visually engaging would be just as interesting.
Thanks for the report
My first new car was a 1979 Mercedes 240D whose engine was based a design from the 1930s, a far cry from todays diesels
The biggest Mercedes diesels I have driven were the 37.4 L 10 cylinder turbo charged unit fitted in the Canadian Forces Leopard tank propelling the 42 ton vehicle up to 80 km. off road. An experience I still vividly remember.