Look on the bottom about 6" in from the passenger side. If there's nothing there, you'll have to remove the lower hose. In the mid '90s some of the radiator suppliers were making them so cheaply that they would crack inside on the sealing surface the first time you opened the petcock, then you'd have a drip about once every five seconds. Rather than improving the quality or addressing the problem, some of them chose to just leave the petcock off.