I would expect the replacement to have the same number of wires as the original if the replacement came from Mercury unless the 6 wire stator was not original to the engine. Can you describe the wire colors and their placement on the engine? For a 4 cylinder Merc it should have a red, a blue, and two yellows, and maybe a black ground wire. I have seen some aftermarket stators from CDI to use a 6 wire stator for both 6 cylinder and 4 cylinder engines, they just tie a blue and red to engine ground in the 4 cylinder application instead of connecting them to a switch box.