90 z24

I'm having trouble figuring out what one of the coolant hookups on the throttle body connects to. (I'm putting a new engine in a car I didn't take apart.) One is taken care of by the metal line that runs across the front of the engine to the water housing. I've used up all the hoses, and as far as I can tell, there is nothing else to hook up. Haynes and scouring pics of 2.8 and 3.1 engines have not wrought useful.