Hi Caz, I am new here too. ( my first post ) hello to all!
in regards to your new wants, I can help you with what you are after.. I do car alarms, GPS, parking sensors and GPS radio, camera etc. I am loaded full of info!
I currently own two D22's str's. both silver.
one a 2006 3.0Di and now a brand new 2.5 Cr. (time for me to move the 3.0 on.. however I am starting to think it is going to be a VERY regretable sale
as I am in the business of car accessories, I have fully kitted out my babies. I have fitted rear speakers in the 3.0, which I think is the same as yours, and in the rear doors, the speaker grills are already there. well, let me tell you, after a lot of time installing, not to mention finding speakers 'thin' enough to fit so the window doesn't rub when it comkes down, you can't hear them. "what"? you ask! well, when the doors are closed, (you are Driving) the rear seat covers them up! Grrr. take this into consideration. however, behind the rear seat, there is loads of room for a massive amp and an active sub woofer..
so needless to say, I used to cruise arround with the bottom of the rear seat out.. hah sounded GREAT!