This is not currently supported. Website access restrictions can be defined per function, but not per asset group. You can define customized Dashboard tabs for your admins so they don't need to view numbers or lists which are not relevant for them. A Dashboard tab can either be global or personal. Global tabs will be visible for everybody who accesses the web console, personal tabs will be defined per user.
Asset group based access restrictions are a feature on our customer wish-list, but we don't have a release date yet.
