SQL Question - Removing Part of a Field

I've got a SQL table I've imported into Visual Studio LightSwitch 2013 that came from Microsoft Dynamics Great Plains 2010. Everything looks great except for Phone Numbers...they are all in a 14 digit format (last for digits for extension number) and LightSwitch cannot parse this with its own Phone Number data type.

I was wondering if there was a SQL command where I can run against the phone number columns (Phone1, Phone2, Phone3 and Fax) that would remove the last for digits. Currently they show as 00000000000000 . I am thinking if I can remove those last 4, LightSwitch will parse correctly.

Thanks...
Brian