Ford 2003 Mustang Workshop Manual page 2646

3. Check for loose clutch disc lining rivets.
4. Use the special tool to check the maximum allowable runout of the clutch disc.
5. Use an emery cloth to remove minor imperfections in the clutch disc lining surface.
6. Check for wear or rust on the splines. If necessary, clean them with an emery cloth.
7. Check the clutch disc (7550) for cracking, scoring, discoloration or other surface marks. Install a
new clutch disc as necessary.