[mcf57]

Well, I can't really speak for a 2008 Passat, but I replaced the factory radio in my 2003 Passat and it was relatively easy. I put in a JVC head unit that had a lot more features than the factory unit including mp3 CD, SIRIUS, USB, & AUX. I suspect you are doing it for similar reasons.

I got my JVC unit from Crutchfield and they supplied all the needed hardware adapters and tools to not only remove the factory unit, but to also install the new one. Lifetime support for it too. I was surprised at how easy it wound up being and would do it again with them. Now, I later wound up getting an amp as well, but had that professionally installed for about $75 cause that involves being connected directly to the car's battery and going through the firewall or something like that.

ALso had some Polk db series speakers professionally installed too. Probably could of done that myself as Crutchfield supplies instructions for that too, but I didn't really feel like it and had a gift certificate to Best Buy anyway. So I let them handle it.