I have a 1992 Mercury Black Max 150 V-6. I want to add a water temperature gauge and I see that it already has a temperature sending unit in one head that has a tan wire that goes to the instrument cluster. It also has a temp sensor in the other head that activates the warning horn when it over heats. I traced the tan wire from the temp sending unit to the instrument cluster, and it just has a ring terminal on the end that is not connected to anything. I'm assuming that the temp sending unit with the tan wire that goes to the instrument cluster is there for installing a temp gauge. However, I'm unable to find any documentation for gauges that say they work with that existing sending unit. Does anyone know if that sending unit is intended for a gauge...and if so, then what gauges will work with it?? Thanks in advance.
