WEST BERLIN, JUNE 28 -- Inside his dark booth on the plaza between the Brandenburg Gate and the remnants of the Berlin Wall, Reinhard Lutz, an officer in the West Berlin police border patrol, went just slightly over the edge tonight.

Lutz was madly hand stamping everything in sight -- passports, pieces of the Wall, postcards, hands, a hat. Anything you held out, he would happily imprint with the red-and-green stamp of the East German border guard -- a souvenir he got from an East Berlin colleague.

"This is the fun, crazy time," Lutz said. Big chunks of the Wall are crumbling before bulldozers. Streets that were dead ends for 28 years are reconnecting. Neighborhoods suddenly make sense again.

This evening, 50 hours before both Germanys eliminate all controls along their border, four guards -- two from the East and two from the West -- were hanging out in their booth at the Brandenburg Gate, watching Berliners and tourists wander back and forth from one country to another, unimpeded.

On Hauptstrasse in the northern suburbs of East Berlin, the neat, wooden guard booths erected after the opening of the Wall in November were tightly shuttered. Traffic flowed freely on the three-lane street. Entrance to another country was only evident in the change of the street's name to Kopenhagnerstrasse on the Western side.

Only three weeks ago, a foreigner crossing from the West to the East had to wait in long, slowly moving lines to show a valid visa to border guards. Today, no one bothered to check.

Before the Berlin Wall opened, crossing over to the East was a frightening ordeal. Guards used mirrors to inspect underneath cars. Visitors were forced to change at least $20 into nearly useless East German marks.

Passing through Checkpoint Charlie -- one of only two openings in the Wall available to non-Germans -- was a tense trial administered by guards well-trained in piercing stares and mistrustful growls.

In November, as the Wall crumbled, so did the veneer of the border guards. They seemed as bewildered as everyone else, as rules on entrance and exit visas changed almost daily.

By the year's end, border-crossing stories were the talk of Berlin. A guard smiled! A guard asked me for a cigarette!

Early one December morning, an American reporter was the first motorist through Checkpoint Charlie. The guard who was opening his booth lifted the gates, set up his desk and finally flipped on the fluorescent bulb that hung over the traffic lane.

"And God said, 'Let there be light,' " he said. He laughed. And then he said it again.

In January, another guard inspected the reporter's car and found an East German high school history text, a book with 800 pages detailing every action of each Communist Party Congress in the country's 40-year history.

"You can keep that," he said, "No one needs those anymore."

Security measures tightened again in March as the outgoing Communist government tried to boost its election hopes by cracking down on the import of campaign materials from West German political parties. Hundreds of thousands of posters, banners and leaflets were confiscated.

On Easter weekend, the new, freely elected East German government announced a gift: All controls would be lifted for three days.

The laws were never seriously reinstated. Last month, late one night in the midst of the onslaught of Western consumer goods to the East, a new visitor appeared towering over the guard booths at Checkpoint Charlie. The Marlboro Man reigns supreme at the crossing now, his 15-foot-high image obliterating the dreary, gray face of the old way of life.

As late as last week, a few guards insisted on checking travel documents. When one threatened to turn back a foreign visitor, the tourist loudly told a friend, "Don't worry, he's history in 10 days."

The guard heard and replied softly, "Don't make fun."

Today, inside the booth, an East German guard cracked jokes about his impending unemployment.

"It's all for fun now, but in a few days, no more job," he said. "Unemployed. I'm good at stamping things."

The guard, who refused to give his name, said he realizes that those who had orders to shoot to kill anyone who tried to escape from East Germany will not be popular in the new, united Germany.

"Thank God I never had to follow that order," he said. "I was in kindergarten when the Wall went up in '61."