I have some more questions regarding a Nav retrofit on my 2003 X5. I wanna make sure I get everything right, and all the necessary parts before I start pulling my car apart. My first question is:

1. Is the radio module necessary for the Nav and Monitor to work or if I don't install one the only thing that won't work is the radio? The thing is I want to also install a CD changer and TV module as well and I am not sure if the radio module would be required for these to work. The reason I am asking this is I never use the radio and the module is damn expensive!

2. If I do need the radio module, would the radio modules from the UK or US work in Australia or are the frequencies different? I read somewhere on the forums that this is something I should check, but I can't seem to find the answer anywhere. If the radio module is necessary I am assuming I will have to buy old style to new style radio adapter since I have a 2003 X5. Any ideas on where I could buy one?

3. Lastly I looking to buy a Video module from an X5world forum member. However this video module is from the US. Once again, would a video module from the US work in Australia or will I have trouble with the TV frequencies etc.

Thanks for any help and sorry if these questions are stupid or obvious. This is big a project and I don't want to have any useless, but expensive parts on my hands.

Cheers, Phoenix.