Another day - another update....
Today I went to a local wheel shop (Revoloution Motorsport) and I ordered some genuine OZ centres for the wheels (£60 for 4 caps!!!! FML)
Then tonight I met up with a bloke from the 1 series forums and he very kindly fitted my Alpine audio upgrade for me (new tweets, new mids and a 4 channel amp which also powers the 2 under seat subs along with the mids and tweets) the sound is now very much improved over stock and after driving home I now I have a headache from the bass!
No pictures as of yet, but all thats visibly different is that you can see the aluminium speakers behind the door speaker grilles and I now have tweeter pods on the doors.
My BMWP discs also turned up this afternoon so I mocked up the 6 pots and BMWP disc under one of the OZ's to test brake clearance - there is loads of room and they look like this (fills the wheel nicely):
Oh and its currently doing 550 miles to a tank!