Press the nail heads outward and it depresses the latches to allow the nav to pull straight out. Pull the antenna wire straight off. Swing the 2 latch levers to the side and the big plugs come out. Pry the cover up at the back and lift it off. The drive is held with 4? small Torx screws (T7 or T8) IIRC. There are also 2? ribbon connectors to carefully unhook. Then reverse to install. Run the OS V32 disk if needed.