Hi again, we are wrapping up our 1988 Baja Project...and it has been a big project. We have the Mercruiser 454 mag 4 bolt main and have a water temp sensor in the water thermostat housing and an oil pressure sensor on the back of the motor by the oil filter. We have left over wires that our manual states the tan w/ blue line is for a water temp sensor and a solid light blue wire for oil pressure. Does the motor have add'l sensors that we need to purchase or are the ones we already have hooked up sufficient? How many oil pressure sensors and water temp sensors should the motor have on it?