I can just about garauntee the mouting bolts for the springs to the frame will need to be torched too.
You probably know all this already wyliek, but with a 4" lift, to do it right, you will want to drop the transfercase cradle to help decrease the severity of the drive shaft angle. A good idea would be to rebalance the drive shafts too. They are balanced from the factory with-in spec, but you've changed that spec/severity of angle by adding the lift. You may or may not have to modify the front exhaust crossover to get full articulation of the front driveshaft, it will be close, although you should have duals on a cucv.
Brake lines will not need to be extended with a 4" lift, although you will probably have to bend the bracket up a little where it attaches to the rear axle.
Since you're trying to get the pitman arm off, I'm assuming you're putting on a drop arm. One last thing to prevent bump steer is to add sway bar drop brackets. Big difference! The key is to keep the steering geometry the same.
Oh, you'll want extended shocks too, and a heavy duty steering dampener makes a difference, especially with larger tires.
Make sure all drag links, tie rod ends, axle u-joints are tight too. A set 33x12.5's will fit beautifully!
Good luck. You're going to have a sweet looking, and safe handling truck!!
The only bad part is that you won't have a pit crew to do it for you like mangus580!!
