I don't think it would be that easy to activate the DRL in the US version of the NAH now that I've looked at the service manual. The DRL's relay is located in the right front of the engine compartment kind of near the engine coolant reservoir. I don't see any kind of relay socket or wiring in that area so I would assume that the wiring harness for the US version doesn't have that connection.

I think DRL do help with accident prevention and it's a shame the US version doesn't have them. BTW, the service manual explains that the DRL only run at half power so they wouldn't be that big of a voltage drain.