1. Disconnect your Mini PC from all power sources and unplug any attachments.
2. Flip the unit over and remove the four screws from the bottom plate.
3. Remove the bottom plate from the unit.
4. Remove the two inner rails from the unit.
5. Locate the four short screws in your product box.
6. Use these to attach the inner rails to your HDD.
7. Place this into the PC enclosure, making sure to connect the HDD to the existing contacts and screw the inner rails into place.
8. Replace the bottom plate and screw to secure.