After playing to full houses during six performances at Warren Arts in Morrison a month ago, "Steel Magnolias" is coming to the Park Theater Saturday and Sunday. The play is set in the fictional small town of Chinquapin Parish, La., and revolves around Truvy's Beauty Spot, where the ladies of the neighborhood meet to get their hair done, socialize and dish the latest gossip. The 1989 "Steel Magnolias" movie featuring Sally Field, Julia Roberts, Dolly Parton, Olympia Dukakis, Shirley McClaine and Daryl Hannah was based on this play by Robert Harling.