I'd like to revive this conversation. Is there anyone out there who knows about something like this? Please let me know. Thank you.

I have long been a fan of schematics and the lack of conscious design inherent in most, the form of text instead arising from requirement and contrast with the technical illustrations. Some very interesting older documents (manuals, articles and schematics) can be found on the one electron site.

Many of these types of manuals are for companies that prefer not to make them public. However, there are technical textbooks with good typography. Good usually means unobtrusive, though.

If "technical manuals" refers to in-house manuals or instruction manuals, good design often isn't the highest priority since they aren't marketing pieces. But you might look for pieces produced by companies that view design as being important (Apple, IBM, Knoll, etc.).

@Karl Stange Thank you. Those are awesome.