Good to see someone else thinks the same way I do.
I had the Nylon spaces at first but they split after about 400 miles. So then I simply went to the Tractor shop and bought 4of 3" tall cone shaped bump stops. I sat down and carefully cut a flat top to make them 2" high. I simply slip a crowbar between the leaves to spread them enough for install and removal, they come with a stud moulded into the rubber which fits thru the hole easily. The ride is quieter and smoother. From the pic you can see that I have a 3" gap at the upper stop which usually is only 1/2" when unloaded...yes the truck has been shackle dropped 6". I usually take them out when not carrying any loads. I am about to try drilling the upper spring with a cobalt drill to do the same with it. I just use the airbags to do the extra lift when going in and out of driveways when I have the trailer on...I don't use a hitch extension, the drawbar is our landing.

I hope this helps.