9. Logic flies out the mini
After the preceding steps the logic board will now slide easily free of its metal jacket. Note that both memory cards can be left in place for this operation. The black L-shaped pieces on the circuit board are heat pipes to conduct heat away from the CPU and graphics chip, toward the cooling fan and exhaust slot.
10. Rotate to release
The PSU is held in place by just one screw, easy to identify with the logic board removed. But first, you must remove the figure-eight mains socket. A tiny hairclip-style retainer slides out, allowing this socket to rotate 90 degrees anti-clockwise and be teased out. The whole PSU itself can be liberated easily after this by drawing out through the chassis.
11. You’ve been framed
One final screw is all that remains and then the upper-drive frame can be removed. This occupies the space originally populated by an optical drive when the unibody Mac mini was first designed. Apple had always allowed for a second hard drive here, in the Mac mini server edition, and the mounting holes are just waiting for your second drive.
12. Cracking good job, grommet
The new upper-position hard drive (or SSD) is held in place by four rubber grommets and set screws, supplied in the kit. Insert each of the grommets into existing holes around the sides of the frame. Attach the custom SATA ribbon cable from the kit onto the bare drive. The SATA edge connector is asymmetric so it cannot be inserted the wrong way.