Garmin StreetPilot, two maps, display only one map

Hi All,
I want to add one map to my C530 unit, but I don’t want to overlap and display two maps at the same time. Does anybody knows how to hide Garmin original maps and show only the new map made by openstreetmap using my gps device?

Never mind, I think I found the answer. After reading the manual more carefully, I notice that under settings, maps, map info, I can enable or disable maps.