Rathbone lists M104 as Detroit American. I don't see any information about the company though. Bus, or anybody else know about the company or if this is the M104 wrench?

I also have the other oddball, chances are I'll never know where it belongs, but perhaps it has been ID'd from a picture?

See American Harrow in Rathbone for company info. I haven't seen any part list picture of your M104 wrench. I don't know where
Rathbone got his info.

Thanks Bus, I was looking through those Harrow companies. Does sort of have a American Harrow appearance to it. Be nice to see a pictured parts list of the M104.