I just bought an 82 Chevy with a 12" lift and 3" body lift. It has 42" Super Swampers. I first of proably many questions is, How can I fix the steering. I have to turn the wheel about 1 full turn to get the wheels to cooperate. When I drive it I am constantly sawing on the wheel to try to stay straight. Any help is greatly appreciated.  

That's a lot of lift. are there any steering correction devices in place? for example, Superlift offers a 12-inch lift for your model truck and it includes a raised steering arm, raised steering block and drop drag link to address steering issues.

since you bought the truck as is you should also make sure that it doesn't have lift blocks under the front springs. this is a cheap and unsafe method of gaining lift and will affect steering and handling.

if you're unsure if your truck has the items listed above you should consult a 4x4 shop/mechanic and have them inspect the vehicle.  

most likely the joints, tie rod and drag link, it may also be complicated by the bushing in the steering box or could even have loose bolts holding the box to the frame, the frames, crack around and near the box.

ya need a drop pitman, raised streering arm and a Z style drag link to make it steer and adjust correctly with 12"