Editing map location

Hi,
I am having a particular problem about the map-address combination.
Our official address is showing a bit away from our actual location (google maps hasn’t updated it yet, I guess.) In order to get the pin on the map correctly, I have to enter a different address which cannot also be done. So I thought about a roundabout: leaving the official address on the widget as it is and change the code within the widget to point to the right position. Although I looked a lot into the codes, I couldn’t manage it.
Could you tell me how to edit the map position without changing the address shown in the form?
Thanks.