The base L320 RRS (series 1) radio is the 6CD - 565. The higher spec models like the TDV8 and v8 Supercharged I think have the highest spec ICE system.
It is easy to put in a double din system and bypass the rest of the cars systems but you need to be able to connect the standard steering wheel controls (I believe an interface unit is available) - however the radio runs the clock in the cars system so you loose this and with a different radio you may not be able to go into the dash command menu to change preferences as this is done through the radio steering wheel controls - so if you are happy with your selected command settings then all is OK.
The other way to get around these issues is to mount the original radio somewhere else in the car extending the wiring and putting in an autonomous radio in the dash - or just have plugs where you can plug in the original radio if you need to make changes to the command menu.
Garry
REMLR 243
2007 Range Rover Sport TDV6
1977 FC 101
1976 Jaguar XJ12C
1973 Haflinger AP700
1971 Jaguar V12 E-Type Series 3 Roadster
1957 Series 1 88"
1957 Series 1 88" Station Wagon
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