Sat Nav Retrofit

Hi guys,

So I have a 2007 2.7D S-Type XS and I'm looking at adding some of the optional extras that weren't added at the factory.

One of my first upgrades is a touchscreen sat nav.

I have trawled through the forums and there's conflicting advice some say it's plug and play, some say it's impossible.

From what I gather the stype either has the sat nav wiring loom or it doesn't. So when I pull my standard stereo out, how do I know if it has the wiring loom? Pics of with loom and without would be amazingly helpful, because I don't know what I'm looking for.