During their August 31 show at The Canyon in Agoura Hills, CA, Chevy Metal were joined onstage by a number of special guests. Among them were Dave Grohl (Foo Fighters), Gene Simmons (KISS) Sebastian Bach (ex-Skid Row), Scott Ian (Anthrax), Phil Demmel (ex-Machine Head, etc.), Rudy Sarzo (Quiet Riot, etc.), Brian Tichy (ex-Whitesnake, etc.), Stephen…