2000 Ford Windstar coolant leak above thermostat - Does the crossover tube screw in or just plug to manifold?

On a 2000 Ford Windstar, the coolant crossover tube typically screws into the intake manifold. It doesn't just plug in. However, there might be an o-ring or gasket involved to ensure a good seal. You'll need to visually inspect it to confirm. If you're replacing it, make sure to use a new gasket/o-ring if one is present to prevent leaks.