On the surface, Guns N’ Roses and Metallica‘s mammoth 1992 co-headlining tour made perfect sense. Booking the two biggest rock bands in the world for a joint stadium trek behind their recent chart-topping, multi-platinum albums sounded like a license to print money. But when the double-header commenced on July 17, 1992, it was instantly fraught with dysfunction and tension between both bands — and it foreshadowed in no uncertain terms their radically different trajectories. Metallica and Guns N’ Roses were riding high on the success of the self-titled Black Album and the twin Use Your Illusion…