These split collet/shims are for adjusting the front ride height on SY's (Shadows) and SZ's (Spirit/Spurs).  You are not limited to stock thickness availability.  We can make these to any thickness you want.  
There is a 2:3 ratio between shim thickness and the amount it raises a corner: i.e. a 1/2" collet set will raise a corner 3/4".  The factory service manual limits total shim thickness to 1.0".
$45 for 2 pair. This means 4 pieces of the same thickness - enough to do the same size stack on both sides of the car.