All extreme and zq8 have a lower stance of 1.5" to 2". I have a 03 zq8 and I put 2" lowering spindles on it and 3" inch blocks cut down to 2.5". It still sits a 1/4" higher in the back which is what i wanted. I have had no problems with my lowering, but every once in a while my front tires will hit the inner fend but only on major bumps. Thats only the inner fender which doesn't effect anything. I would go with the spindles on your because the are farely cheep and easy to put on. They also ride and handle a lot better than springs would. Let alone the alignment issues with springs.