I run emissions (EPA, Euro, etc.) test cycles for a diesel (and natural gas) engine manufacturer. (Medium duty, and heavy duty engines primarily... up to 16 liters.)
I do have to wrench some also. So, at least it's not all sit down work. An injector change here, turbocharger change there, aftertreatment work, engine changes, etc. We don't do any major work in my labs testing cells/rooms (time is big money in my lab), but that work does go on elsewhere in the building. (I've done that work also.)
So, I guess you could call me a mechanic.
I've read every response to this thread. Very nice to know.
Cheers.