kilo7

Hi all, I hope someone out there can help. I have not long bought a galaxy, 96 p reg, It has an aftermarket stereo fitted which to be honest is sh%t so I wanted to change to maybe a cd changer etc, however i pulled out the old one to find the wires have been butchered Can anyone provide details of what coloured wires from the galaxy do what, positves etc, any help would be great. I appreciate this may have been covered previously i have looked through the posts but couldnt find anything, ive been all over the net and can only find american sites and diagrams, which all relate to the plugs which is what im missing, I basically have the wires all loose and need to identify which ones are for what, HELP!!!!