I need to install an air gap for a new dishwasher in an older house. The old cast iron sink does not have extra holes for the air gap, so it has to go on the counter next to the sink. Is there a special air gap or extra device that will direct any water spit out by the air gap into the sink rather than going onto the counter? I can't be the only one with this problem, but I've tried several stores and no one seems to have or know of any product other than the same old white plastic air gap sold everywhere.