I talked to them and they went back after the install and put on Shockwaves all the way around instead. I have had air ride on trucks before and the ride was awesome. I plan on 'bagging my 87 GN in the future. You can go cheap for about $800 total or go with the Air Ride Technologies shockwaves for about $800 front and $800 rear, plus about another $500-600 for compressor, tank, valves, gauges and switches. If you are just going for the look, you can go cheap with a bracket/bag set up- which is pretty much bolt in, but you will have to weld in a shock mount for the front. They tend to be a little squishy. If you want the best performance...go with the Shockwaves. I plan on going with the Shockwaves on the front and Firestone 2500# bags/brackets in the rear with copper lines. You can get the Firestone bags for about $50-80 each and the bracket kits are about $50 for the front and $50 for the rear. The compressor will run the most as it is the key component. Save yourself a big headache and get a 100% duty cycle.
Have a few other issues to work out before I install my air ride(about to rebuilt engine and suspension). I talked with the guys at Hzemall and they are very helpful.