Hi-line OEM 'upgrade'

[rab60bit]

I'd like to give my Contemporary SE Hi-line an OEM-like update, in particular the sat. nav. I've had recent random issues with the radio and eventually found that the aerial ISO plug on the tuner in the wheel well had almost corroded away (I've asked a question on here about fixing that earlier in the week, so far no reply from anyone - could do with getting this finished!).
Once everything is back working normal I've already got a BMW widescreen IMG_0574.jpgIMG_0573.jpg to replace the original unit (is this a straight swap out once I've trimmed the two top fastening lugs - do I need a double Din bezel with this new unit?).
In order to get the full benefit of the 16:9 monitor I believe I need a BM24 or 54 tuner/amp + pin-changer jumper lead and Mk4 DVD sat. nav. drive all of which should be plug and play.
The new bordmonitor has a 'phone button, is this a bluetooth enabled facility that requires some more bits?
Finally (without confusing me too much further...) what's involved if I want to add a Mk2 splash screen.

I've seen some really helpful how-to's here on this subject in the past - got any short cuts to these?