Primus + Ween Join Matt Stone + Trey Parker to Play Lots of ‘South Park’ Songs + ‘America F–k Yeah’ LivePrimus + Ween Join Matt Stone + Trey Parker to Play Lots of ‘South Park’ Songs + ‘America F–k Yeah’ LiveWeen joined in at the 'South Park' 25th anniversary concerts too.Joe DiVitaJoe DiVita