Has anybody put an aftermarket headunit in the G6? I've been going to place after place, best buy, circuit city.. everyone telling me something different.. so then i went to this highend custom shop and they told me that it doesn't need the gm class II harness, so basically the chimes and car vitals don't run through the factory unit. Also if someone has one installed, can you post a pic, i would like to see the dash kit mounted. By the way.. i'm getting a DVD Flip out and navigation installed