ANAHEIM, Calif. (AP) _ A woman's body was found after a newspaper received a letter in which her husband allegedly confessed to killing her because she didn't understand his premonitions and said he left a list of 54 people who ''will be punished.''

''Last Friday night I shot and killed my wife,'' began the five-page letter, allegedly from David Schoenecker, 48, that was received Thursday by Orange County Register columnist Bob Emmers.

Schoenecker was arrested by a Montana sheriff Friday afternoon, wandering in the Clearwater National Forest just inside the Idaho border. He was carrying a .357-caliber Magnum revolver but did not resist, authorities said.

''There was no hatred - I loved her - but the action was necessary because I have a purpose and one that cannot have an interruption or interference,'' the letter said.

''Gail reasoned only in black and white or good and bad. She never dealt in the grey or devious world. A world where I now totally exist,'' it said.

The letter, dated Monday and handwritten on stationery from a Missoula, Mont., Travelodge, said there was a possibility that the body of Gail M. Schoenecker, 40, had not been discovered. The writer included the couple's address and advised Emmers to contact authorities.

''I never got anything like it before. It gave me the chills,'' Emmers said.

Police Sgt. Chet Barry said Friday that police had confirmed that the body they found Thursday afternoon in the Schoenecker's home was that of Mrs. Schoenecker, an elementary school teacher. The cause of death had not been determined, he said.

Schoenecker had been seen Sunday when he checked into the Travelodge and apparently spent the night. His car was found abandoned Tuesday in the Lolo National Forest, about 60 miles west of Missoula, and cabins in the area were searched, Mineral County Sheriff Wade Van Gilder said.

Van Gilder flew by helicopter over the rugged Bitterroot Mountains to drop ahead of Schoenecker in the Clearwater forest, then walked back to meet him, said Montana Highway Patrol officer Rick Seemann.

Schoenecker had followed a natural course from the Cedar Creek drainage where he left his car, into another drainage and then over Hoodoo Pass into Idaho, Seemann said. ''He wasn't sure where he was headed,'' Seemann said.

The area has many homes and mining claims and is served by a well-traveled road, so Schoenecker had been reported several times on his trek, Seemann said.

Mineral County deputies were notified Friday by Anaheim police that Schoenecker bought camping gear in Missoula, probably on Monday, a sheriff's spokesman said.

Investigators didn't know exactly what he bought, or where, or whether he has outdoor skills. Anaheim police would not say how they learned of the purchase.

The letter said Schoenecker killed his wife because she didn't understand the premonitions and ''images'' he had about people who had ''done wrong or evil'' against him.

''Several times I tried to explain these 'happenings' to Gail (my wife) but she dismissed them. I was never understood. I knew that as these feelings and 'pictures' continued to occur and repeat that I had to prepare a way, develope a plan, make arrangements. And I have done so.

''Now, I had to eliminate my wife. She wouldn't believe me. She wouldn't even listen. So in order to keep her from finding out, I developed a separate plan or storyline that totally misled her, but it did make her happy. She was very happy on Friday.

''Gail suspected that we were missing a great deal of money. She also was upset about several of my trips. Recently she started to figure that I must be doing something else with my time and our money.''

The letter suggested that the chemical engineer may intend to kill other people.

''I've left a list - a partial list. Not everyone on the list will receive total punishment - but they will be punished,'' the letter said. ''The images in my mind shows me exactly how and when and where the punishment will be delivered. It has to be done.''

Police searched the couple's home and found a list of 54 people, the majority of whom live in the Milwaukee area.

Anaheim police had contacted about 75 percent of the people named on the list, Barry said. Several of those listed had gone to Custer High School in Milwaukee with Schoenecker, Lt. Marc Hedgpeth said. His wife also was from Milwaukee.

Schoenecker's ex-wife, Kathy Schoenecker, was on the list; they were divorced in 1977. Her current husband said by telephone from Milwaukee that his wife was shaken. She and Schoenecker had two daughters. Police said Friday they didn't know the whereabouts of the women, Terry, 20, and Tracy, 22.

''He is absolutely not a violent person,'' the former Mrs. Schoenecker said in a brief telephone interview with The Milwaukee Journal, which did not give her present last name.

Schoenecker was senior class president of Custer High School and the 1959 yearbook recounts a 55-yard touchdown run he made in a key football game.

Milwaukee police Detective Jim Gauger said Friday a picture of Schoenecker had been distributed to all police stations in the city, and officers have been notified to pay attention to residents on the list.

Police in suburban Wauwatosa, Wis., began surveillance Thursday night on the residences of two people on list, said Lt. Greg Nauman. ''Neither could understand why they were on the list.''