CROSS-DRESSED TO KILL

When Guiding Light told Frank Beaty his character would be revived just a few weeks after supposedly passing away this summer, the actor was thrilled. Then he was told he'd be coming back not only as Brent Lawrence, the rapist, but also as Brent's nutty, avenging alter ego, Marian Crane. ''I about died!'' says Beaty, 27. ''I thought, a woman? How am I going to carry that off?'' The answer: charm school, ballet class, and some pretty amazing prosthetics. Now this Wong move has turned into a complex, risk-taking story line that is upstaging the Atlanta native's non-drag work. ''Even I'm jealous,'' Beaty laughs of his Tootsie role. ''Marian is on screen more than Brent is.'' But even after three hours of makeup, this hunk is no babe. ''I make a horribly ugly woman,'' Beaty admits. ''But I have a great figure and nice legs. I've gotten compliments.''