Jeanne Mandel has an idea how the federal prison at Eglin, Fla., can best make use of the talents of her husband, ex-Maryland Gov. Marvin Mandel, when he begins serving a three-year sentence there Thursday.

"He could take over the processing of the Cuban refugees" who are being housed at the Air Force base which adjoins the prison, she said proudly yesterday. "Marvin is a great administrator, and he even speaks Spanish -- fluently."

"I don't know what the rules are," the two-term Democratic governor said in response to his wife's idea, "but I'd like to be active, to be involved in a work program. But that's not my decision."

Mandel, who was convicted in federal court in 1977 on charges of mail fraud and racketeering, is spending today -- a day he once thought might see him seeking the Democratic nomination for the U.S. Senate -- trying to decide what clothes and other goods to take with him when his long-delayed incarceration begins.

Going to the minimum security prison in the Florida panhandle "won't take any great adjustment," Mandel said yesterday as he scrambled to clear up his affairs. "The last three years have been the same as prison, except I've been with my family. And even that was quite limited."

His wife will remain in Annapolis and run the mom-and-pop consulting firm she and Mandel formed after his conviction meant he no longer could practice law.

"Jeanne will try to keep everything together," said Mandel, puffing on his ever-present pipe. Asked when he might be paroled, Mandel said, "I don't speculate about that."

A Justice Department spokesman said that Mandel and his codefendants, as first-offenders, technically will be elegible for parole as soon as they begin their sentences. But normally the U.S. Parole Commission schedules a hearing 120 days after an inmate begins serving his sentence.

Jeanne Mandel said she plans to visit the former governor "as often as business and family will permit. But there is no way you'll get me out of Maryland." She said she "loves" the consulting business, and in response to a question about whether it is lucrative, she said, "the sun is beginning to shine."

Jeanne Mandel said that while "adversity has made me stronger," she is "constantly concerned" about the health of her husband, whose first trial was delayed after he suffered a mild stroke. He said yesterday he "feels fine, but I get a little tired."

But slowing down isn't the answer for a man "who has worked 14, 16, 18 hours a day for 30 years," she said. "He needs a challenge" and that is why she sees working with the refugees as "a real opportunity for them (prison officials) to utilize him. I hope they appreciate what they're getting."

Mandel insisted he isn't bitter about going to prison. But he quickly added: "I don't like the idea. But I can live with myself, with the knowledge that I never hurt anybody. One day the truth will come out, and will vindicate what I've said all along."

Mandel was convicted of accepting gifts from his five codefendants in return for his help, as governor, in enriching them by obtaining extra racing dates for a small race track that they secretly owned.

He said he was given a choice of four prisons, and picked the one in Florida "because in cold weather, I'm very susceptible to problems. I've never seen the place, I don't know where it is. Somewhere near Pensacola." (Eglin is 60 miles from Pensacola and 10 miles from Fort Walton Beach, near the Gulf of Mexico.)

As for comments that he is going to a "country club" prison, Mandel said, "I will be more than happy to change places with anyone who thinks it's a good deal."