yeah, he has 20's, I misread in the mag...
But I don't see any reason why you couldn't, You might have to get a different offset so it doesnt hit the bedside when its tucked, and a custom built notch. The only problem would be the driveshaft hitting the back of the cab. I know that the LT-1/ ZF 6-speed owners had to clearance the back of the cab (a couple of whacks with a sledge), to take off the lip. But that will only gain you an inch or so. And if a bodydrop is in the future, you can pretty much forget about it.
I'd plan a rearend gear change too, cause your acceleration will be affected dramatically. I'm sure the STS guys would know more, but thats my .02
You still have your Air ride setup for sale? I'm interested.