Pass Database Instance through .gsc file specifiation to gINT v8i

I am a developer who has inherited an application that creates a fence diagram by passing specifications from a .gsc file to gINT.  The database has been upgraded and we are now trying to connect to a specific instance, where previously we connected to server only.  I am able to pass DbServerName, EnterprinseDb through the gsc file but cannot pass an instance.  The connection in gINT would be Server\Instance... is this possible through a .gsc file?