How do you remove a stereo from a 1988 Jaguar XJ6?

Each of the four doors had a 3.5" Phillips. The two under the back seat were 4". You need to remove the door panels to get to the speakers. Good instructions in the book by Hayes (I recommend this because there are several tricks to get to the hidden screws). Once door is completely disassembled you can access the speaker to remove and it is easy to simply cut away the foam and put a 4"coax in the same space. From the car there is no noticeable difference as you don't have to change the grills at all. Under the rear seat you can replace with 5.25" coax but it requires drilling new screw holes and using after market grills