Position the PSP so that the UMD Device is facing upwards.

With the UMD drive open, locate the aluminum UMD eject bracket. Pinch upper arms inwards to dislocate them from the UMD door.

The UMD eject bracket can now be easily pulled out.

Gently pry on the left side of the UMD door to remove it.

Be careful not to break off plastic knobs that secure the door in place, otherwise the UMD Drive will not open properly.