Following a month of eclectic pairings for “Mash Up Mondays,” Jimmy Kimmel Live! will cap off the series with a performance of “Regulate” by rapper Warren G and saxophonist Kenny G. The debut of “Kenny and Warren G,” as Kimmel has dubbed them, performing the west coast rap classic originally by Warren G and the late Nate Dogg is the fourth and final installment of “Mash Up Mondays. Performing “Regulate” is particularly timely for the rapper, who will be celebrating the 20th anniversary of the song with a week-long tour next month that will make stops in Washington, Oregon, California and Vancouver. The tour follows up a reissue of the triple-platinum album “Regulate G Funk Era.”