I got the cables from different suppliers: quadlock extension from here: http://incartec.co.uk/pages/Product.aspx?P=3651

The janus kit from *bay (€49) (actually a lot cheaper there compared to his own webshop)

Steering wheel adapter from *bay (£19 or something) including the cable from the box to ...

The kit I bought can be had unpainted, which is how we got the one that's in the other x5, and with a different alpine unit.

The only downside to all these different fascia kits, including the one i bought, is that they never seem to be 100% perfect following the shape of the dashboard, we went ...

This is what one of our x5's looks like with an alpine ine-s900r using "janus" double din kit:
Total install time took about 2 hours