Ford 2003 Mustang Workshop Manual page 1653

Installation
1. NOTE: The crankshaft pulley must be installed within four minutes after applying the silicone.
Apply silicone to the Woodruff key slot on the crankshaft pulley.
Use Silicone Gasket and Sealant F7AZ-19554-EA or equivalent meeting Ford
specification WSE-M4G323-A4.
2. Using the special tool, install the crankshaft pulley.
3. Install the bolt and washer. Tighten the bolt in four stages.
Stage 1: Tighten the bolt to 90 Nm (66 lb-ft).
Stage 2: Loosen the bolt one full turn.
Stage 3: Tighten the bolt to 50 Nm (37 lb-ft).
Stage 4: Tighten the bolt an additional 90 degrees.
4. Lower the vehicle.
5. Install the accessory drive belt. For additional information, refer to Section 303-05 .