I have a 2002 SS with all the factory stereo and I was in the Future Shop looking at stereo's yesterday and the salesman scared me away with a rumor about a $150 harness that I "absolutely need because it runs the computer and the airbags etc..." blah blah blah it was all a crock. Now that I have looked into it I find out that it just keeps the chimes working, I can reset the oil message another way. Do I even need this? I don't care about the chimes at all...
I also want to add an amp and sub in the back so I am wondering if there is one harness that does everything? GMOS-04?
or do I need both the GMRC-02 and the AOEM-GM24 amp harness?
or could I get away with just the AOEM-24 amp harness since I don't care about my warning chimes at all?

Thx.