to remove the old cd player
you will need to remove the centre aircon vent.
use two screw drivers and at the TOP of the air con vent there will be two tabs which you have to pull down with the screw driver.
and then when the aircon vent is out remove the wiring harness for the emergency light.
now you will need a 12mm? socket and you look through the vent that you removed and at the bottom somewhere there will be two bolts.. once on each side. remove these two bolts and becareful not to drop them!! then slowly pull the whole pod towards the back of the car..
unplug both wiring looms and thats your factory cd out of the way.
now the factory cd is only single din but has a front face is a bit larger. there is a cover on top of the cd to cover the empty space up.
you can buy single din covers or trays its up to you what you want to do... they are available from toyota