Caster Adjustment
WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 1995 Chevrolet Caprice, 1995 Buick Roadmaster, 1994 Chevrolet Caprice, 1994 Buick Roadmaster, and 1993 Chevrolet Caprice. However, it is still accessible from the selected car via links, so may be relevant.
Remove, add or transfer shims at bolts securing upper control arm shaft to frame. See Figure . One shim pack can be thicker than the other, but not by more than .40" (10.2 mm).