Ford 2003 Mustang Workshop Manual page 300

Check the needle bearings for correct positioning.
2. Position the new spider in the driveshaft yoke.
3. Using the special tool, press the bearing cup to just below the snap ring groove.
2. NOTE: Use the yellow snap rings supplied in the kit to assemble the universal joint (U-joint). If
difficulty is encountered with the yellow snap rings, install the black snap rings, as required.
Remove the driveshaft from the special tool, and install the snap ring.
3. Repeat Steps 1 and 2 to install the opposite side of the driveshaft yoke.
4. Inspect the driveshaft slip yoke. Install new if necessary.
5. Repeat Steps 1 and 2 to install the remaining new bearing cups, spider, driveshaft slip yoke,
and the snap rings.
6. NOTE: Do not strike the bearings.
Check the U-joints for freedom of movement.
If binding, strike the yoke with a brass or plastic hammer.
7. Install the driveshaft. For additional information, refer to Driveshaft in this section.