PRIME CONCERN : MAI’s plan to take over Prime Computer goes before the analysts. But many doubt whether Bennett LeBow can raise $1.3 billion to do it.

Bennett S. LeBow and other top executives of MAI Basic Four met Wall Street analysts and the press Monday in an effort to overcome the nagging public doubts that threaten the company’s takeover bid for much-larger Prime Computer.

Outlining financial details of the proposed deal, the investor and his fellow executives seemed to make some headway with the analysts. But several still expressed doubts that Tustin-based MAI could raise the $1.3 billion needed for the acquisition at the current price or beat a rival suitor if a bidding war breaks out as some believe is possible.

“I believe a man more when I see him than when I just read about what he wants to do,” said Barry Bosak, analyst with Eberstadt, Fleming & Co. in New York. “But some of the questions are still unanswered.”

The company needs to gain credibility, particularly with large institutional shareholders, if its pending tender offer for the Natick, Mass., maker of mid-size computers is to succeed. Prime last week rejected the MAI offer as inadequate and also disclosed that it had been approached by an unidentified third party about a friendly combination.

LeBow, the normally publicity-shy financier who is chairman of MAI and a takeover specialist, said he might consider raising his bid if Prime officials began releasing confidential information about operations that indicated a higher price could be justified. “We’d seriously consider it,” he said.

But he added that a more detailed look at those finances might also indicate that a higher offer was not justified.

The executives forecast that the combined company would have $2.1 billion in annual revenue and operating income of $253 million to $293 million, for what they said would be a healthy operating profit margin of 12% to 14%. They said the new company would have total debt of $1.66 billion and equity of $110 million.

LeBow said MAI had sought a buyer for itself during the spring and summer and had several proposals. But the company had rejected the offers because they were “not at the price levels we want to achieve for the company,” he said.

The company then decided to seek a merger partner because of the executives’ belief that the computer industry is going through a consolidation after which only larger companies will survive, he said.

William Weksel, a MAI director and a partner in LeBow’s investment partnership, said MAI is “unequivocally” not for sale. Some analysts have speculated that LeBow and his associates have been trying to provoke Prime to take over MAI so they could cash in their shares.

The MAI executives have said the Drexel Burnham Lambert investment banking firm has given them a letter stating that it is “highly confident” that it could raise $875 million in high-yield “junk bonds” to help finance the deal.