Where are the MAX and MIN fill lines on my '97 DeVille?

I inherited my Grandmother's Cadillac and was told to monitor the coolant
levels because my Grandfather once suspected that it had a small leak. It
has not ran hot, and the temps are never over 212* at highway speeds
and/or in town. Engine runs like a sewing machine, but I am concerned that
without knowing where the fill lines are I will not have a point of reference
when checking the coolant level. The reservoir is easily accessible but I
cannot seem to find the fill lines in question. Thanks in advance.