The clock harness for 1970 does end up in a female/female plug, but what you are missing is a short harness that goes from male/male to male/female. I personally have never seen one, but one can easily cobble one together with the now reproduced radio-side radio plug and a standard male/female trailer connector. If you want to match the dual female plug on the clock harness, you'll have to find another clock harness and use that plug.