By Zach Haberman

A gangster-turned-rat stunned a federal courtroom yesterday as he described how two reputed mob cops helped kidnap a low-level thug and hand him over so he could be tortured and killed by the Mafia big he tried to assassinate.

Septuagenarian stool pigeon Burton Kaplan sang about the brutal 1986 slaying of Gambino associate Jimmy Hydell, and how NYPD detectives Louis Eppolito and Stephen Caracappa helped ensure he paid a horrific price for his failed hit on bloodthirsty Luchese underboss Anthony “Gaspipe” Casso.

“[Casso] asked me to call my friend to see if they can arrest him and turn him over . . . not to kill him, to kidnap him, he wanted him alive by all means,” Kaplan testified yesterday at a trial in which the two ex-lawmen stand accused of a host of mob-linked crimes.

Kaplan, 72, said Casso was a “homicidal maniac” who wanted Hydell alive so he could take a medieval revenge for the failed hit attempt.

The cops’ involvement in the vendetta began when Casso asked Kaplan to contact his mobster pal Frankie Santoro Jr., and have him approach Eppolito, who is Santoro’s cousin.

Casso wanted Eppolito and his partner, Caracappa, to use their police connections to figure out who shot him.

Kaplan said the officers complied with the request – and even did it for free.

“[Santoro] comes and meets me with a manila envelope with a bunch of reports from crime-scene investigation and a bunch of pictures,” Kaplan said. “I opened it and looked in it and there was a picture of Jimmy Hydell.”

Kaplan told the court the information from the secret police files was “very helpful, very efficient” – and it sealed Hydell’s doom.

Casso later offered the cops $35,000 to help kidnap Hydell, Kaplan said.

In October 1986, about a month after the hit attempt, Eppolito and Caracappa arranged to outfit a car to look like an unmarked detective’s vehicle, complete with a flashing light.

Kaplan said they pulled Hydell over, made him get out of his car and then forced him into their trunk.

Santoro then took the car and drove it to the parking lot of a Brooklyn Toys ‘R’ Us store – with the two cops following behind to keep an eye on him.

Along the way, Hydell kept banging on the inside of the trunk, angering Santoro so much that he got out and punched the kidnapped man a few times to shut him up, Kaplan testified.

Finally, Santoro handed the keys over to Casso, who took vicious revenge.

Kaplan said Casso brutalized the man by shooting him about a dozen times in places that caused the maximum pain, but did not kill him.

During the torture, Hydell begged Casso to dump his body “in the street” so he would be found and his mother could collect life insurance on him. Casso lied and said, “Yes.” Hydell’s body has never been found.

Kaplan said Casso was impressed by the performance of Eppolito and Caracappa, especially how they watched over Santoro after the kidnapping.

Kaplan said the honeymoon didn’t last. In 1986, when Casso asked Kaplan to have the cops – whom he dealt with only through Santoro – pull the file on Nicholas Guido, they demanded $4,000 for the job.

Casso balked.

“Gee, I just gave them a $5,000 bonus for that thing with Jimmy. Tell them they are getting pretty greedy,” Kaplan said yesterday, quoting Casso.

Kaplan said that, although the cops did pull the information, the mob eventually used data gleaned from a source at a gas company to locate Guido.

Unfortunately, they got the wrong information, and wound up whacking an innocent man named Nicholas Guido.

Kaplan followed that tale with bombshell testimony linking Caracappa to the only killing in which one of the two cops is accused of actually pulling the trigger.

The witness said he paid the pair $70,000 to rub out mob associate Eddie Lino, who was believed to also have been involved in the failed hit on Casso.

Kaplan said that while he was in a hospital recovering from eye surgery, Eppolito visited him, told him the hit was complete and explained how he did it.

The cop used a familiar tactic in the hit – he pulled Lino over, Kaplan said. After Lino stopped, the cops went up to him, asked him his name and then asked him to “look at the floor.” When Lino looked down, Caracappa shot him, Kaplan said he was told.

“I asked, ‘How come Steve shot him?’ ” Kaplan testified. “[Eppolito] said ‘Steve’s a much better shot.’ ”

Earlier in his long day of testimony, Kaplan told of how he first started working with Santoro and the two cops. Kaplan said he and Santoro met when they were inmates at the federal prison in Allenwood, Pa.

“He said [his cousin] had a friend . . . they could help me if I got any problems, physically help me.”

Kaplan said he first did business with Santoro’s cop cousin in 1986, when Casso decided jeweler Israel Greenwald had become a liability.

Kaplan said he was involved in a racket with a Hasidic banker from Williamsburg named Joe Banda, who could help turn stolen Treasury bills provided by Casso into cash.

With the help of Greenwald, Banda laundered a bill in Europe that netted a quarter of a million dollars for Casso and Kaplan.

But Casso became convinced Greenwald was going to rat out the operation, Kaplan said.

So Kaplan turned to Santoro, who said his cop cousin and the cousin’s partner could help him with his problem.

Kaplan said he paid $25,000, and Santoro told him it would be easy “without any doubt.”

“They would take him on the highway. They would pull him over with the flashing light, they would say he was wanted for a hit-and-run,” Kaplan said about the cops’ plan.

He said they finally took Greenwald to a parking garage, where Santoro said he shot him.

A few years later, after Santoro was killed, Kaplan became close to the cops. One day they met in a cemetery, and recalled the Greenwald hit.

He said Caracappa had one question. “Just off the top of my mind, what did you pay Frankie for that thing we did?” Kaplan said, quoting the cops.

Kaplan said he lied and told the detectives he paid $30,000.

“Frankie only told us $25,000,” Caracappa allegedly responded.

“He must have put the extra five in his pocket,” Kaplan recalled saying. The only response from the two detectives in court came when Kaplan described a falling out he had with Eppolito – and how they later became friends. “I liked him then and I like him now,” Kaplan said, forcing Eppolito to lean back in his chair and laugh.

Quotes from mob turncoat Burton Kaplan’s testimony:

* ‘I asked, ‘How come Steve [Caracappa] shot him?’ He said, ‘Steve’s a much better shot.’ – recalling his discussion with Eppolito about how he and Caracappa allegedly killed mobster Eddie Lino (left)

* ‘[Casso] asked me to call my friend to see if they can arrest him and turn him over . . . not to kill him, to kidnap him. He wanted him alive by all means.’ – recalling his discussion with Luchese underboss Anthony “Gaspipe” Casso about getting accused mob cops Louis Eppolito and Stephen Caracappa to assist in a hit on Jimmy Hydell, who had tried to assassinate Casso

* ‘Maybe ‘Gas’ should have paid the $4,000 and he would have gotten the right Nicky Guido.’ – quoting Frank Santoro Jr. (above) about Casso’s decision to not pay the two cops for information about where mobster Nicky Guido lived