My trusty old El Camino came from the factory with the crappy Air Shocks for load leveling. They were only good for 12 months or so and it was time to replace them. After several rounds of that, I switched to Air Lift 1000 part number 60733 that fit up inside the rear springs.
https://www.amazon.com/dp/B000CFS02S/ref=pe_2640190_232748420_TE_item
Just remove the large bolt through the lower shock connection, drop the suspension lower than possible with the shock in place, and the entire spring comes out with no issues. I switched to them 20+ plus years ago. It was necessary to change to Bilstiens to get a good ride, but that is easy.
The air bags seem to last 8 or 9 years, and then they develop a leak. So pull the spring, and swap out the bag. I was sure that last time I did that I only replaced one airbag and I had a spare on the shelf. Nope, just the box for the part number, and some of the hose and fittings. Crap. The one airbag sure enough has cracks in the side, and leaks air instantly.
So I figured perfect time to buy local. I called several dealers and no one had them in stock, but one dealer mentioned that the Air Lift company REQUIRES any dealer to install them, the customer can't install them. They are not allowed to sell direct to the customer.
Summit Racing and Amazon don't seem to care about those rules. Since I am a Prime member, I ordered them from Amazon to get the free shipping. The local dealers will miss out on the sale. I tried.
Advance Auto Parts does sell them to customers, but they had none in stock, and it was going to be the 24th before they could get them in and they were going to be 108 bucks to boot. So I save 20 bucks from Amazon and get them tomorrow.
So Amazon will deliver them to my door tomorrow.