Those guys from That '70s Show are threatening to bail out of the hit Fox comedy if they don't get more money.

Ashton Kutcher and Topher Grace are the only two members of the young, ensemble cast who have yet to agree to appear on the show's seventh season.

Both actors are still in negotiations with the show's producers at Carsey-Warner even though their co-workers -- Laura Prepon, Mila Kunis, Danny Masterson and Wilmer Vladerrama -- have agreed the stay on through the 2004-2005 season.

Kutcher, who plays dim-witted Michael Kelso, told E! Online that in order for him to return, the producers "better treat me right." Grace -- who plays straightlaced Eric Forman -- could not be reached for comment yesterday. Contracts for Kutcher and Grace expire at the end of next season.

Officials at both Fox and Carsey-Warner said they do not comment on contractual matters.

That '70s Show is one of the most unheralded success stories on Fox. The sitcom, now in its fifth season, has proved to be one of the most flexible shows on the network and tends to nab viewers even when it is moved around the schedule.

With more than 100 episodes in the can, the show went into syndication earlier this year and airs about six days a week on various local stations.

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