I guess you could use shims, but you still have the same problem of rotating the steering system.  When the steering system rotates forward (or backward) the WHOLE steering system moves with it, including the linkages between the knuckles.  This means the linkages will get pushed down.  In the case of a high steer system, that will push the linkage into your springs if you have leaf springs, or in the case of the stock push-pull setup, it moves linkage closer to the ground giving even more opportunity for damage.  But even beyond all this, it will greatly affect your caster angle, unless as I said earlier, you cut off the knuckle ball, rotate it, and weld it back on.  And, you had better be a really good welder or have a really good welder do it for you.