I put up a post somewhere which showed removal of the cd player in a D40.
It's something along the lines of gently pry the top coin tray out and then remove the screw you can see then the rest of the panel down to the switches its just clipped in. Obviously be careful pulling the clips but it comes off quite easily and then you can choose whether to remove the power connectors for the fan switch etc, there maybe be enough cable for you not to have to do that. Then take the 4 screws out that surround the head unit and it is out.