fitting after market unit to audi with bose system

[the_bb]

audi a4 cab 3.0 b6 2003

can you help im finding my old 2003 satnav a little old with no mp3 no dvd and no preouts . im looking to fit a high end ish double din uni without the satnav but with everything else . how will this affect my bose system ???

cheers