No, he’s not just the TV pitchman for Right Guard: Method Man will guest-star in at least one installment of Boston Public next month, playing a malodorous record executive who’s hot to sign Aisha (ex-American Idoler Tamyra Gray). For those about to rock, the episode will also feature a performance by Lifehouse in Doyle’s Bar…. Cybill Shepherd will be moonlighting in the two-part season finale of ABC’s 8 Simple Rules… in May. She’ll play the newly divorced sister of Cate (Katey Sagal) who reignites the ol’ sibling rivalry when she’s invited by Paul (John Ritter) to hang with the Hennessys…. Andy Richter gets to control another universe — specifically, The WB’s On the Spot — when he graces the new improv comedy on April 17…. David Carradine appears in the April 27 episode of Alias as a mysterious monk in Nepal who delivers some crucial Rambaldi info to Sloane (Ron Rifkin). Sorry, no kung fu moves were used by Carradine in the making of this episode.