If this is the same '80 truck in your other thread with a 6" lift, you probably just need to grind the angle stops on the CV. The pinion angle probably isn't too bad. Post some pictures of what you have going on before you go messing your steering all up (because then you will start a new thread asking why your truck wanders across the lane and your steering wheel isn't centered any more).
I have had factory front shafts work just fine on trucks with twice the suspension lift you have by grinding the angle stops on the CV.
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