Dont fool yourself. SASing a truck isnt cheap. Expect to be well over $5-7k deep, probably more to be DD reliable. Much more if you dont do it all yourself. many have tried to do it cheap and have failed miserably and then its double the cost to fix it.

I have 9" of suspension lift on my truck (and a 3" body) and Ive ran the shit out of it at Rancho many times. I also drive it 35k+ miles per year. I have almost 100k on the lift and you know what Ive replaced.. 1 ball joint and all the tierod ends (only because they were still stock at 180k miles)... BUT I did change the pitman, idler, and all 4 ball joints when I did the lift. Ive never had a single problem from my IFS lift. Its actually a lot stronger than most give it credit for.

FTS (Full Thtrottle) makes kits up to 15" but their kit is ugly as sin IMO.

Swing on over to GMFullsize . You'll learn a ton.