Haven't used it myself but looks like they designed it to be just shy of the bed floor. If you've got a shortbed 88-98 you'll have to notch the center bed support out, no big deal. You probably already have it notched in the middle for the pumpkin.
My bolt-in notch only gives me about 3.5" travel because my truck has the 14 bolt SF which has a larger axle housing. I've already bent the bottom of the notch on both sides (I'm static, not bagged.) If I went to that Super C I could get up to 6" more travel, though the pumpkin will probably bottom out on the floor at about 2~3" or so short of that.