To remove the factory fitted cd player you need some radio removal keys. These can be bought from Halfords / Motor World for around £4. They are called ISO Removal Keys.
You will get 2 keys in a set. 1 for the left & 1 for the right side of the radio.
Simply slide the keys into the holes on the radio, pull slightly outwards and pull.
There will be 3 plugs on the back of the unit, Power, Speakers and aerial.
I will post some pictures very soon
Ash