In the teaser you see Boss Hogg say he would much rather welcome the plague then Bo and Luke back but the line or the scene isn't in the episode.
Just after Bo and Luke return, before Coy and Vance leave, when they two pairs of cousins exchange their keys, Vance can be heard saying "here you go Byron" as he throws the keys to Coy.
Bo: Well, let's get out of here.
Luke: Hey, I think the General needs a gentle hand today.
Bo: Yes...so you'll drive.
Bo: Say, Luke, what is that ugly looking thing sticking out from underneath that hood?
Luke: Well, I'd be danged if it ain't a Cooter Davenport.
Boss: And the winner of Miss Tri-County area is--(sees Bo and Luke walk in) Bo an' Luke Duke!!!!!!
Bo: Well, this isn't exactly a visit.
Luke: We're home for good!
Rosco: He knows that you're an early bird and him being a worm plans on catchin' ya. I think I said that backwards.
Boss Hogg: You've always been backwards.
While we never do see the return of the live action Coy and Vance, their animated counterparts would continue for a few weeks in new episodes of CBS's Saturday Morning cartoon, The Dukes, which premiered the month before. For the cartoon's second season Bo and Luke (voiced by Tom Wopat and John Schneider) would replace Coy and Vance.
Tom Wopat and John Schneider are returned to the opening credits for this episode. Byron Cherry and Christopher Mayer are also featured in the opening credits for the final time.
Coy and Vance Duke are written out of the series within the same episode that Bo and Luke are written back in. After a brief meeting with 'proper' cousins Bo and Luke, the replacement Duke boys are gone by the first commercial break, never to be seen or even mentioned again! Although the pair had never proven overly popular, many fans were disappointed that the four cousins never really got to team up together for one adventure together. After the re-introduction of Bo and Luke, the episode itself is a very much run-of-the-mill affair, with the change of Duke boys just being rather stuck on the beginning.