I agree with Steve, AirRide really is the way to go, and they've proved their kits on the track. We are very happy with their kit on our Chevelle. I'll also post a photo of my old Impala, which was also on air. I like it because I could run larger diameter wheels, and could set the ride height where it was best during driving, or at a show. And nothing's cooler than the right stance on an old Impala, tucking big diameter wheels!
You can see some of their products here:
http://www.driverzinc.com/accessories.html or their website:
www.ridetech.com