Hi ,I am happy to be a new member here and feel very at home with Utah friends, my question is in the title of this article , after looking true every book on the systems , all over the internet there are not even one place that mention this subject, what I get on my gps screen is Kilomètres and indur it is Miles but it is not lit so pressing the knob many times and seaching all over the books and the net ; no answer , should done simply by pressing the Miles button . anyone have an idea where I can get instructions on how to do it or is it simply a option that is put and set for good depending where you live?