usually with a dbl nut on the spindle, the top one jams/tensions the lower
one from loosening. if it's how I am picturing, you use an open/box end on
the bottom nut, while spinning the top nut off with a socket (or another
open end if there is room). you dont even touch the threaded spindle of
the shock.

__________________
-- raymond~
47º 34'N 122º 18'W