Run, DMC and Jam Master Jay are mad as hell, not about to take it anymore, and quite ready to let you know about the bad rap their rap is suffering. On the one hand, things couldn’t be better for the trio of 21-year-olds from Hollis, Queens: the group’s third album, Raising Hell, is tightlike-that in the Top 10, and their latest single, a cover of Aerosmith’s “Walk This Way,” performed with Steve Tyler and Joe Perry, is barreling through the Top 20—albeit without the support of many chart-oriented stations, such as the biggest one in their hometown. As they travel across the U.S.A. on their “Raising Hell” tour, Run-DMC, as the headliners of an all-star rap package that includes Whodini, LL Cool J and the Beastie Boys, are drawing crowds large enough to sell out arenas coast-to-coast. But on at least a half-dozen of those shows, what they’ve also been drawing is trouble.