Did you break off the welded coller on the screw? You wont get much of a turn with that on....But you will have to take the scew out to get that off...Just make sure you mark the position of where is at before you do so. From MY
stock position I turned mine 1.5 turns in. When you do that you will have to back off the idle screw also as the power screw will raise the idle and rev it out or run away at the worst. Mine never ran away or even came close. And the truck should be running. The nut on the idle screw is a 10mm. Id loosen that up and get ready to back it out as you turn up the fuel screw.. To be safe turn the fuel a 1/4 turn at a time until you get to where you want at the same time backing down the idle to keep it there.