Ok guys lately Ive been thinking about maybe upgrading the audio in the GP. Not sure what it would take or any of this never touched the audio in a car before. What are some things I should look at? Also what type of cost am I looking at? I have an 05 GTP with the Monsoon system in it now. How hard is it to mix and match parts? Am i looking at having to replace everything or just certain compents?

Lots of questions hopefully you all have some answers for me. Thanks in advance