Welcome to the forum. Actually, there are quite a few trucks being built rat rod style now. I've seen them on other forums too. Generally, the theme follows a lowkey flat painted body, simple interior, solid wheels, dropped stance, etc.

Hotroddaddy is right about the air suspension. It has to be done right to be safe and handle well. Take a look at AirRide Technologies and Suicide Doors. They are just two of the companies involved in air ride components. My Son knows more about bagging than I do, and I asked him whose system he is using, and he said he combined components from various companies to get the system he wanted. So I guess each company has a particular part that is more desirable than some of the others and you may have to mix and match.

As for cost.........wild guess would be in the neighborhood of $ 1500 - $ 2000 by the time you buy compressors, tanks, lines, bags , mounts, switches, etc. But that is simply a guess buy a novice. Much will depend on what you want the bags to do, and how much you can fabricate yourself.

Just understand that bags are not without their problems. They can leak and blow, although not something that happens every day. A certain amount of "engineering" is involved to get them to fit and work right, and also to last.

I'm sure others will be along who know more, and will give you better info.

Don