I too was wondering if there was a Dreadnaught connection. Looking at my selection of Dreadnaught wrenched I note they are very similar in their methods of stamping as the Ford wrenches shown in this thread. Edited to add: I got my answer here:
http://progress-is-fine.blogspot.ca/...eadnaught.html
As well, the CMP (or was it carrier?) manual shows the double open end wrench set which is held together by a little metal bracket which tightens up and holds the wrenches together. I picked up one of those sets which had a red bracket instead of khaki, and the wrenches are all dreadnaught.
Derk
Perhaps our favorite surplus store is where you want to be looking for CMP wrenches. There are bucket loads of wrenches out there.