Series 500, 700, 900
Adjust caster by turning nuts at rear of strut rod. Lengthening rod increases caster. Shortening rod decreases caster.
NOTE:
Because of manufacturing tolerances, it is possible to run out of threads on strut rod or cause front spring to be cocked in its seat and rub spring tower. Only when this happens is it permissible to shim unevenly at upper control arm.
If shims are changed, check camber.