Jim,
I cranked up the torsion bars to increase the front end height and eliminate some of that GM rake the H2 inherited. You can crank the TB's as far as they will go with the stock keys, or you can replace the keys and crank them even higher. The more you tighten the TB's, the firmer the suspension becomes and the harsher the ride. My preference is to adjust between stock and max height, which helps to eliminate body roll, nose diving and mushy ride.
Several years ago, a GM mechanic told me not to crank to torsion bars up because they would fatigue sooner and would have to replaced. Later, I read the same thing in one of the 4x4 mags. Regardless what they said or I read, I raised my Z-71 anyway....6-7 years ago and no problems.
Crank 'em up.