I just picked up a very similar wrench from ebay for $9, plus 48 state shipping of course. It's a 14-17mm not the 15-17mm posted above, but does say W. Germany. Hard to see in the photo but it does have the underlined o in No.Not belonging to an original toolkit, but a nice period correct* addition: an 15-17 bent ring spanner. Super handy if you need to replace that starter motor, it's about the only way to get the top bolt out with a full engine bay.
As with original ring spanners it has shiny chromed ends, and it uses the 'No' with a small line under the zero.
* it does say GERMANY, and not W-GERMANY, which has me wondering. Could it be post unification but made with older tooling that was modified to take out the "W-" part?

Erik et al,Notice how the head of the "Heyco" printed pliers (Image below, most right one) has sides that are conical.
All images of pliers or toolboxes show small pliers with a short parallel section first; the conical section starts higher up.
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compare head shape with these toolboxes:
View attachment 119402
Holy moly, man, that is a lot of tools! What's your plan with all of those? You should clean some up and either put them up here or on Bring a Trailer. In general a well-sorted set of tools can pay for at least some of the repairs/upgrades I know you are doing.Erik et al,
this picture you quoted above is a picture of some of my tool collection. I’m getting to the bottom of my cars and collections and moving this stuff along.
If I can help by looking closer at some of these I’d be happy to dig them out and get them sorted. I don’t need all these tools. They are all used and far from perfect but if it helps i can certainly confirm finishes and markings. I’m definitely mixed them up incorrectly in their trays and I just have no idea where to start!