Ford 2003 Mustang Workshop Manual page 2877

7. Remove the second gear needle bearing.
Inspect the needle bearing for wear or damage. Install a new needle bearing as
necessary.
8. NOTE: Reposition the output shaft on the press with the input shaft end facing upward.
Remove and discard the snap ring, then using the special tool, remove the third/fourth gear
synchronizer assembly, the third gear synchronizer blocking ring and the third gear.
Inspect the gear for broken or cracked teeth. Install a new gear as necessary.