I replaced the Wave radio in my 2002 new Mini with a Boost radio, which adds a CD player and better sound quality. It also enabled me to use the carkit interface I had for my Nokia phone carkit.
When I bought my 2002 Cooper, it had a Wave radio and a CD changer. In 2002, that was totally cool (you could listen to these new-fangled silvery discs as well as to your existing collection of cassette tapes), but in 2008, I'd rather be able to stick a CD in a slot in my dash. Also, I still have the interface lying around that will connect my Nokia bluetooth carkit to a Mini. Through a radio Boost, that is,
and since the Wave and Boost radio's have different connections, I'd have to do a swap if I wanted to be able to take calls in the car the save (and legal) way.
I got the Boost radio from a Dutch supplier (WheelsOnline). Because the Wave and Boost radios have very different physical connectors (but they are compatible electrically) I had to get a conversion wiring harness. This I got from the same supplier where I got the carkit interface, NewMiniStuff in the UK.
To show what I mean, here are the connections on the back of the Wave and Boost units:
Left, the connection on the Wave unit, right the connection on the Boost unit. The pins on the Wave radio are round, whereas the pins on the Boost radio are flat "plates".
If you are interested in the entire process, have a look at the Flickr set. For here, I'll finish of with a picture of the end result.
Update 1/5/2010: Link to Picture section no longer valid, linking to Flickr set now.Comments
The details are in the linked Flickr set. Not so much about actually opening up the dash of the car, that's readily available on other sites. I think I originally found them on http://mini2.com. I've since done it numerous times and don't really thin about it anymore.
Some information of how you did it would have been useful:)