Tool & Die makers made them by hand.
I have seen proto type car panels such as fenders, hoods, etc, panel beaten by hand to produce the prototype model, when the car was finished you could not tell the difference in that and the eventual production model.
I was at the MG factory when the MGA came out.
Many of the Tool & Die apprentices were 'poached' by US companies on the completion of their apprenticeship.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.