Some time ago, I bought a Mercedes publication on e-Bay titled "Schluessel-Liste Nr. 7 fur DIN und Normteile." This is basically a guide to the "N" part numbers (screws, washers, nuts, etc.) used on cars in the 60s. I have found it useful for assembling my 280SL project, like figuring out what screws to use to hold the throttle linkage to the firewall. You find the part in the EPC or paper book, then look it up in the Liste and find the description, size, length and finish of the screw.
I am wondering if this would be of interest to others, like available on this web site. I am willing to investigate the alternatives to make it searchable online. It is not copyrighted.
Attached are the introductory pages and sample data page.
If you look on the data page at the first line under the heading DIN 84, you will see a number, 000084 002104 in the first column. This is the N part number. To the right you will see that it is a 2mm screw, 25mm long, with a galvanized highly polished finish. From the heading, you know that it is a lens-head screw.