Remove the six screws located on the underside of the system with a 4.5mm Gamebit screwdriver.

Turn the unit back up and lift the top cover.

At the top is a capacitors shield. Make sure they're discharged before removing it. (Capacitors can hold charge for a long time, switching the power switch on while unplugged should discharge them)

This is the front panel, requires a ribbon cable to be unplugged.

This is part of the cartridge ejecting mechanism.