Ford 2003 Mustang Workshop Manual page 1170

4. Disconnect the engine wiring harness retainer and position it aside.
5. Remove the bolts, studs and the valve cover in the sequence shown.
Inspect and clean the sealing surfaces.
6. NOTE: Apply an eight millimeter bead of silicone gasket and sealant at the intersection of the
engine front cover and the cylinder head.
To install, reverse the removal procedure.