An aging Mafia underboss turned government witness today and told how mob families from Cleveland, Milwaukee and Kansas City each commanded a voice at the meetings of the Teamsters union's multibillion-dollar Central States Pension Fund.

Testifying in a low, gravelly voice, Angelo (Big Ange) Lonardo, 74, said the three Mafia families all backed a $62.75 million Pension Fund loan to buy two Las Vegas casinos in 1974 for the simple reason that "everybody could benefit from it."

He was asked how.

"Through the skimming . . . stealing money from the casinos," Lonardo explained in matter-of-fact tones. "We in Cleveland would get a package every month."

Lonardo's testimony came at the two-month trial of eight men accused of secretly taking control of a string of Las Vegas casinos owned by the Argent Corp. in the early and mid-1970s and skimming more than $2 million from them.

The heavyset, jowly witness, now serving a 103-year federal prison term, identified the late William Presser, longtime boss of the Ohio Teamsters and father of current Teamsters President Jackie Presser, as the Cleveland mob's man at meetings of Pension Fund trustees.

"He William Presser was supposed to get $1500 a month," Lonardo said. "Maishe told me."

"Maishe" is a nickname for Lonardo's brother-in-law, Milton J. Rockman, reputed financier of the Cleveland mob and a defendant at the casino-skimming trial here of the Midwestern Mafia's top leadership.

Rockman, 73, who also has been named as the Cleveland Mafia's liaison with the Teamsters, stared steadily at Lonardo as he took the witness stand.

Imprisoned since 1983 on a narcotics conviction, Lonardo seemed not to notice. He never used the word "Mafia," barred from the trial as prejudicial, but he readily described himself as a member of a nationwide "organization" with formal initiation rites that has existed in Cleveland since the early 1920s.

A brother-in-law, like Rockman, of the late Cleveland Mafia don John Scalish, Lonardo said he was inducted into the organization in the late 1940s, rising to underboss. In 1976, his uninitiated but highly influential brother-in-law gave him a briefing.

"Mr. Rockman wanted me to know where the money was coming from," Lonardo said. "He always took care of the labor movement and the financial movement . . . He briefed me on how it all started, how the skimming started."

Lonardo then related how California businessman Allen R. Glick had approached Milwaukee Mafia boss Frank (Fancy Pants) Balistrieri in 1974 for support in buying the Stardust and Fremont casinos. Lonardo's testimony contradicted Glick's claims earlier in the trial that he was unaware of the mob control of the casinos until after the purchase.

Lonardo said that Balistrieri, a defendant in the case, "knew Milwaukee Teamsters official and Pension Fund trustee Frank Ranney very well." In addition, he testified, Balistrieri reportedly said he would "talk to the late Kansas City crime boss Nick Civella," who was "very friendly" with another trustee, Roy L. Williams.

Civella, in turn, met with Rockman in Las Vegas, Lonardo said, and "asked him if he could talk to Bill Presser in regards to getting a mortgage for the Stardust."

Prosecutor David B.B. Helfrey asked: What was Presser's reaction?

"That he would do whatever he could," Lonardo replied.

According to Lonardo, the "skim" began to flow in 1974 from Las Vegas-based emissaries, with the Cleveland mob getting a cut of about $40,000 a month. Before long, however, "there was some kind of dispute about the split of the money" Lonardo said. Civella and Balistrieri, he said, had to go to Chicago, apparently around 1975, for an audience with Joey Aiuppa, reputed head of the Chicago "Outfit," and his underboss, Jackie Cerone.

"Kansas City and Milwaukee mobsters , they both report to Chicago -- any troubles they have and things like that," Lonardo explained. In return for their intervention, he added, the Chicagoans "got 25 per cent of the skim money."

Lonardo said he made several trips to Chicago with Rockman to pick up skim money from a former Chicago policeman named Anthony Chiavola, a Civella nephew who earlier pleaded guilty in the case. Lonardo also told of a meeting that he and Rockman had in Chicago with Cerone and Aiuppa several years ago to discuss who should succeed the ailing Frank Fitzsimmons as Teamsters president.

After "Aiuppa excused Rockman from the table," Lonardo said, "We discussed . . . getting Roy Williams."

The plan, Lonardo said, was that with Williams at the helm, Jackie Presser "would become a trustee of the Central States Pension Fund. We told them Aiuppa and Cerone that we could have a lot of favors through the Central States Pension Fund through Roy Williams being president."

According to earlier testimony, however, Williams did not like Jackie Presser and reneged on the supposed deal. Presser, whose father died in 1981, succeeded Williams as Teamsters president in 1983.