Hmm, the service manual makes it look like there's a NUMBER of differences between the Canadian and US models. Seperate sections for lighting in the manual for each. Let us know if it works though. That'd be one heck of an easy mod.
It appears that the relay is missing from the US model, true... However, the service manual also is showing that the combination meter (M24) does not have pins 23 and 13 on the US model, with 23 running to the parking brake switch (M11).