Better to get the bits either divorced if getting separately, or as a pair if married and always handy to have the security codes for the units. You will need a GPS aerial, typically people use Fakra ones off eBay, and you will need an RGB cable .... these are around £70 from Vauxhall I think, so if you can get a complete setup all the better. Oh, and it's a CD70 head unit and CID display you need.
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