[David_Hayward (RIP)]

You might argue that the Ford F60T CMP permanently-coupled tractor-trailer unit was a semi-COE, and used by the British, and Canadians?

Here is a British COE: Autocar Company ‘Tractor 4 x 4 for Mobile Oxygen’, ex USA to Demand S/M 6406 in the batch H 5877462 to 5877475. I also have shots of Studebaker and Federal tractors but they were Normal Control. The Canadians had COE Dodges but the photo in Dr Gregg's book is a rigid truck. The British of course had GMC COE rigids but the only known GMC tractors were NC units.