IMBD has them each listed as "Sorority girl". it is probably in the credits like that. I have not checked. Actually their names are Stacie and Gracie. I found that on this site...
http://archiveofourown.org/works/3570758/chapters/7867970
Jean and Liz Sagal. They were the Wrigleys Doublemint twins for awhile, had a TV show called Double Trouble around 1984/1985 and are sisters of Katey Sagal from Married with Children.
shareInteresting trivia. One was hired at a New York casting call, the other in L.A. They showed up on the set and the director, realizing they had hired identical twins, created the sorority girl roles for them.
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