I own a 98 a4 2.8 quattro and wanna buy a clarion gps system or just hte clarion dvd/mp3 7inch touch screen but ive heard that u have too replace all the speakers if u have bose is this true and has ne one had experience installing head units into there audi with bose thanks guys ik this is a dumb question but i just dont wanna spend 800 dollars and then not have it work correctly.

 

you dont have to replace the bose, although i recommend it.
Pioneer Avic n2