oh nah. I should have tried it out before responding here. I was getting confused as the schema view shows external data sources in a different tree so was thinking an additional path was needed for the container path. Got it working with an ExtGrid with no real dramas.

 new LABKEY.ext.EditorGridPanel({
        store: new LABKEY.ext.Store({
            containerPath: 'Shared',
            schemaName: 'CLIN1',
            queryName: 'HCVRESULTS'}),
        renderTo: 'grid'});