Search around on this and I'm pretty sure you'll find posts on it. When I took mine out I had to break the glue that holds the old one in by going round the edge of the pod between the plastic that holds it in with a knife. There was a little damage to the back of the pod but nothing that's visible from above.
I replaced the originals with Alpine ones - there was a mount in the Alpine kit that fitted in really well afterwards and Araldited in.
From my post that I did on it:
jas025 wrote:Also removed the tweeter pods and prised out the old nokia tweeters thanks to some posts on here.
New tweeters part of the Alpine component set that I bought removed from the default pod that they come with.
There were quite a few different pods that you could use to install - chose the one for flush fitting and then got some araldite to glue them in place.
Tweeters then click into place.
Not installed them yet - one crossover is in place, got to install the other one on the drivers side and then wire them up at the weekend.
Sound from the little pioneer amp that I found is already a great improvement but the sound stage is a little rear focussed because of the lack of treble currently at the front. Looking forward to hearing this when the tweeters are in place!