Ford 2003 Mustang Workshop Manual page 1665

31. Lower the vehicle.
All vehicles
32. Remove the LH valve cover.
33. CAUTION: Do not use metal scraper, wire brushes, power abrasive discs or other
abrasive means to clean the sealing surfaces. These tools cause scratches and gouges
which make leak paths. Use a plastic scraping tool to remove all traces of old sealant.
Clean and inspect sealing surfaces and valve cover gaskets. If necessary, install new gaskets.
Make sure the gaskets are correctly seated on the valve cover.
34. Remove the four bolts and the coolant pump pulley.