When you clean the parts, all of the cool factory markings reappear. The paint marks on the springs, which are not visible in the "before" photo, tell the Krauts which springs to grab from the shelf for a w123 wagon with diesel engine and automatic trans plus factory A/C, in this instance. They had springs for every possible configuration and in Europe, they sold a lot of variations that we never saw.
All factory parts were marked in those days, often with a part number but always with a star. Here is an example next to an aftermarket replacement part, (from parts car):
Old bushings are as bad as I've ever seen:
