How different is the 08 XJ Navigation head unit from the previous ones?

Specifically I'm looking to replace my 07 s-type nav unit with new one that has sirius integrated. Did they completely change the wiring or is a pretty easy swap?


Thank you.

 

The nav unit does not have sirius integrated. It is a seperate sdars module. Not interchangeable from XJ to S

 

Great. Thank you very much for a quick reply.