Mine is located in the intake manifold up near the neck that the upper radiator hose connects to. I have also heard that many temp senders are screwed into the front of the head, maybe someone can varify. You can buy the sending unit at NAPA for certain and probably any other parts store. Some senders have a "nail head" fitting on top and some a post type fitting so take in your old one so they can match it. Cost $10-15.