He has an 06. The foglights are very different than what you have.
You can use HIDs without a harness if you wish. I always recommend a harness when using HIDs to avoid issues with flickering and ensuring the ballasts get powered by the battery instead of the stock wiring. If you decide to go with a harness then you need 1 for the headlights and 1 for the fogs. Other than that, you will have no issues with it being an extra load to the car.