it looks like if you slot the plastic, remove all the metal beneath the climate controls and make metal brackets that hold it in at an angle you should be able to fit a double din fairly easily. I think thats how the guy above did it. I'm going to buy a seperate stock radio to use as a template and give it a go.

 

Can you email me with details (pics) on jakenji@yahoo.com? Thanks. I have a 98 XJ8 with the oldfashioned telephone dialpad.

 

double din will fit - see the picture of my 1999 XJR - it has a Pioneer Nav/DVD player - 7" fitted
I would not recommend doing it to anyone who is not extremely confident in their abilities, my console/ shifter surround is now constructed from Alloy, covered with (fake) carbon fibre, I had to fabricate the little crossmember and relocate airbag controller - Now it is finished - it was worth it - but a very complex job. Sorry, I just saw how old the post was

 

Double din won't fit but here is pic of my JVC NX5000 which suits the car well.