For those WCC owners who have a heater installed, I found a nice heater control valve from NAPA. It is an in-line flow control valve with 5/8 hose barb on either side and is a modern design. It is an injection molded GF reinforced plastic valve that should last the life of the car. NAPA part number is BK-6601141. It accepts a standard rigid wire push-pull HVAC cable. It replaces the metal Motorcraft part # YG-133. I will post a pic when I get a chance.