If you're planning on a 4x4 conversion, I can see the need for the extra hight, sounds like you're just planning ahead. My questioning was more curiosity that anything.
As to the air shocks, the idea is that they're more of a load leveller for when max load is used and the suspension sags. They're only meant as a temporary suspension lift, not so much a permanant thing. I know that guys use them for that, especialy on Mustangs and Camaros, and on a light vehicle, you can get away with it. But I've had to replace plenty of them that blew out from the constant strain for being inflated all the way without a load. It's very rough on them. You might consider an ad a leaf or a similar lift spring on the rear to match the front. But you may still want to hang on to the air shocks, that way if you load it, you're alrady setup.
