2000 Cirrus leak behind fly wheel unknown

There's a tube with an o-ring on each end that goes from the back of the water pump housing on the passenger side to the thermostat housing on the driver's side. Look closely under the thermostat housing first. If there's no sign of leakage there, suspect a corroded core plug at the back of the block. The service manual doesn't show them all, but it's common to find one or two there. The transmission has to be disconnected from the engine and lowered to access those plugs.