On my 2F 86 FJ 60, I have this elbow fitting coming out of the passenger side of the block. It looks to be a cold water return from the rear floor heater. (Please correct me if that assumption is wrong) Puzzling thing is it has a Tee in it with a short 5/16 heater hose that is not connected. PO had it stuck on one or the distributer vents. Which if it were to have water in it would not be good. What is this really and where SHOULD it be hooked up or should it be abandoned?