David, I've wanted to do this ever since I started driving heavy trucks. Unfortunately I only have a pickup nowadays. Once you go to an air ride seat there is no going back! You have to have a flat floor and enough space for range of movement though. Most air-rides I've driven bottom out unless you have the head room to get them up high enough.
There are LOTS of options on these in truck world though. If this one doesn't work out any heavy truck salvage yard will have lots of them at good prices (OEM removals usually).
Hey, on that porch light you got, is it as bright as the pics on the website show? If so I must have one!