Star of Battlestar Galactica Maren Jensen was never known for nudity (she used a body double in Deadly Blessing) but this little known movie from 1979 released in 1981 as Beyond the Reef contains quick as a flash nip slip frontal nudity and rear nudity. I've slowed the videos down and zoomed in so you can see and no body double,
This is nothing to her work with Wes Craven fifth films