RATT’s Stephen Pearcy, Juan Crouceir, and Warren DeMartini reunited and performed a surprise show today (October 1), on the Monsters Of Rock Cruise. The three were also joined by Carlos Cavazo (Quiet Riot) and Jimmy DeGrasso (ex-Megadeth, etc.) Check out some footage that Eddie Trunk (That Metal Show) shared on Periscope/Twitter: LIVE on #Periscope: Warren,…