What actors and actresses appeared in The Smothers Brothers Comedy Hour - 1988?

There was no "The Smothers Brothers Comedy Hour" in 1988. The original run of the show was from 1967 to 1969. There have been various reunions and specials over the years, but no full series in 1988.

It's possible you are thinking of a different show. Could you please provide more context or clarify your question?