Dell Precision Workstation 450 User Manual page 113

1. If you are replacing a drive and the the new drive does not have the bracket rails attached, remove the rails from the old drive by removing the two
screws that secure each rail to the drive. Attach the bracket to the new drive by aligning the screw holes on the drive with the screw holes on the
bracket rails and then inserting and tightening all four screws (two screws on each rail).
1 drive
2 bracket rails (2)
3 screws (4)
2. Gently slide the drive into place until the tabs securely click into position.
3. Attach the power and floppy-drive cables to the floppy drive.