I finally got around to adding the horn that beeps when you back up. Always used the bulbs with the built in speaker, but the HHR uses a different one. So I picked up a separate beeper and taped into the power line on the passanger side. I used an extra nut to secure it to the bolt that holds in the tail light. I haven't found a good place for the ground wire yet, so I just have it jammed under one of the strap tiedowns. Next are the airhorns. It looks like a pain to get to the factory horn, so I may just add an extra button for the new horns. Then, I have an old alarm that I added a selector switch and a momentary switch. When I blip it on the right sound, it resembles an NYC police car. I plan on mounting those 2 switches under the steering column.

 

I finished the wiring, and found a great place for the ground. I just connected it to the end of the bolt securing the side tie down. I added an additonal nut since the factory uses a nut attached to the panal. Although the speaker is technically inside the car, you can still hear it outside.