Airbags and leaf springs?

[muddpile]

I've seen quite a few vehicles where they took out all but one leaf in the springs and then put in airbags. My question is how much adjustability will this give me, and where could I put the bags? The truck is a 72 longbox C10 with the factory rear leaf setup. Also, how low can I go with just bags replacing the coils up front? Basically, I want to bag my leaf truck and keep a big range of adjustability. Thanks!