I have a 1985 Nissan 70 hp. I recently acquired it and noticed there were a couple of wiring issues. The trim wire was connected to the one lead on the heat sensor. Well at least I figured out why the trim wasn't working! But now do not know what plugs in to the heat sensor? One wire is grounded to the head cover and I am perplexed about where the other wire from the heat sensor is supposed to connect. There are no other free wires visible. Where does this thing go?