Ford 2003 Mustang Workshop Manual page 1357

45. Install the oil level indicator tube.
46. Install the LH exhaust manifold.
Install a new manifold gasket.
Install the LH exhaust manifold.
Tighten the nuts in the sequence shown.
47. Connect the lower end of the exhaust gas recirculation (EGR) tube to the LH exhaust manifold.
RH cylinder head
48. Install the RH exhaust manifold.
Install a new exhaust manifold gasket.
Install the RH exhaust manifold.
Tighten the nuts in the sequence shown.