In the summer of 1969, "Hee Haw" moseyed into the CBS time slot occupied by "The Smothers Brothers Comedy Hour." Conceived as a rural alternative to "Rowan & Martin's Laugh-In," the show ranked in the top 20 nationally when CBS pulled the plug in 1971. But co-hosts Buck Owens and Roy Clark, along with the whole Kornfield Kounty gang, sang and joked on in syndication. In 1978, they grinned at the critics in a two-hour 10th-Anniversary shindig, which was videotaped with an audience of invited guests and fans at the Grand Ole Opry House. Mixing nostalgia with new performances by country music's biggest stars, this special edition of "Hee Haw" never misses the funnybone. Here's one for you trivia buffs - Did you know that Kenny Rogers met his wife Marianne Gordon while visiting the "Hee Haw" set? Kenny elaborates and then does himself proud with "The Gambler," one of the biggest hits of 1978. As for Gordon - she's part of the show's tribute to the easy-on-the-eyes "Hee Haw" girls. Junior Samples gets his due in