In this cabaret musical revue lyricist Henry Mach and composer Paul Katz take a grim-sounding theme and make it light, lyrical, insightful, and touching entertainment. Four gay men--two lovers and two loners--reflect on their lives while awaiting the results of their HIV tests. Their sung and spoken monologues trace each fellow's journey from adolescent alienation and confusion to adult self-understanding and affirmation. Though the specter of AIDS hangs over all of them, their musical memories are concerned mostly with the days before AIDS--the era of social and sexual discovery that followed the 1969 Stonewall riots, evoked in a collection of witty and emotive tunes that convey a neat mixture of defiance and self-deprecation and gracefully avoid the subject's potential for morbidness, polemics, or feel-good fluffiness. This brief revival of last spring's sleeper hit reunites the committed, vocally superb original cast--Don Auxier, Dan Turek, George Smart, and Dan Ferretti--who, with the fine guidance of musical director Daniel Stetzel, communicate quirkily believable, emotionally textured characters. Puszh Studios, 3829 N. Broadway, 327-0231. December 11 through 19: Fridays, 10:30 PM; Saturday, December 19, 10:30 PM. $15.