Is your center link horizontal and not higher at either the pitman arm or idler arm and is it parallel to the centerline of the front crossmember? Are your guide rods parallel to the ground or just slightly lower at the outer ends? Are the ends of your steering arms the same distance from the spindle centerline and the same height from the floor on both sides? If yes to all this you may have to pull the springs and then raise and lower through the entire suspension travel by a jack under the front crossmember and watch what is happening. Something at some point is pulling things out of line. These trucks did scrub the tires to a degree when cranked against the lock, usually more one way than the other.
