Ford 2003 Mustang Workshop Manual page 2567

45. Install the special tool.
Position the indicator stem on the flat portion of the reverse servo piston and zero the dial
indicator.
46. Loosen the bolt until the piston stops against the tool.
47. Verify that the amount of piston travel on the dial indicator is within specification.
48. If piston travel is not within specification, select and install the correct servo assembly to bring
the servo piston travel within specification.