Do you have the Premium Audio i.e. is there a subwoofer in the back?
Which harness are you using?
The little wire by the antenna, is it blue? If it's the one I'm thinking of, I don't know what it is but I cut it and taped it up, it didn't seem to make a difference to me.
I can't remember the factory connections now, but what colour are the wires running into the small plug? Are they paired i.e. solid grey and grey with a stripe, purple and purple/stripe, white and white/stripe etc?