1994 740i CD player/speakers

So my family recently bought a 94 740i. Love everything about it, except the musical abilities. The cd player has a six disc changer and is broken, for whatever reason. the speakers are ok, but they are originals from the car so are obviously old. is there a way to install a new cd player and/or speakers without having to mess with the computer in the vehicle? any info would be appreciated.
-fmarion

I have a 2001 and have fooled with all of that stuff to install a mediabridge. Have not got it working properly but no alarm problems. I may have a changer for you.