Archie Reese, San Francisco's defensive tackle, stood inside the Candlestick Park dressing room Sunday where the rain's flow met the reign's glow.

"Dallas," he said, nearly in reverence, "when they come, they will have fire in their eyes after what happened in our first meeting."

Some of the 49ers had said the same thing last week about the New York Giants, who lost, 17-10, here during the regular season. Of course, now the 1981 Giants are like John Brodie: part of 49er history. This is a result of the 49ers' 38-24 victory Sunday over New York in an NFC divisional playoff game.

"If we make some of the same mistakes we made against the Giants, though," safety Dwight Hicks warned, "Dallas will blow us away."

Dallas, of course, is next for the 49ers. Next Sunday, San Francisco will entertain the Cowboys for the NFC championship. The winner will go to the Super Bowl.

The rain continued to fall today, just as 49er opponents have fallen this season at Candlestick Park, where the 49ers are 8-1.

But while Sunday's game is still warm, the recollection of Oct. 11 is just starting to thaw. That was when San Francisco whipped Dallas, 45-14, the Cowboys' worst defeat since 1970, when St. Louis beat them, 38-0.

Now, the 49ers reflect on that other destruction almost as a bad thing. They know Tony Dorsett will probably run for more than the 21 yards on nine carries he managed last time. They know Danny White probably will lead the Cowboys to more than the 192 total yards they had here in October.

They know the Cowboys.

Johnny Perkins, the Giants' wide receiver who also knows about Dallas, was impressed Sunday as he watched the 49ers win their sixth straight game and 14th of their last 15. "I think we'll be watching them in the Super Bowl," Perkins said.

Coach Ray Perkins of the Giants, who caught passes from Ken Stabler and Joe Namath with the University of Alabama, and from Johnny Unitas with Baltimore, was asked if Joe Montana, San Francisco's quarterback, is the best in the NFL today. His response was simply, "Yes."

Montana completed 20 of 31 passes for 304 yards and two touchdowns Sunday. Most importantly, in the first half he completed 15 of 22 for 276 yards and the two touchdowns as his 49ers took a 24-10 lead.

"I was just doing the same old thing," said the NFC's No. 1-rated quarterback. Montana completed 19 of 29 for 279 yards and two touchdowns in the demolition of Dallas.

The San Francisco offense of 423 total yards was acceptable to the 49ers. The New York offense of 346 total yards was not.

"We had several breakdowns," said rookie safety Ronnie Lott, who intercepted two passes and returned one 20 yards for San Francisco's final touchdown.

The two most blatant breakdowns were Scott Brunner's 72-yard touchdown pass to Earnest Gray that tied the score in the first quarter and Brunner's 59-yard touchdown pass to Johnny Perkins in the third quarter that made it 24-17.

The last time the 49ers were in the playoffs they lost, 30-28, to Dallas at Candlestick Park in a 1972 NFC Divisional game.

San Francisco Coach Bill Walsh, a man of offense and a man who tries to keep his pregame quotes inoffensive said: "We have a lot to do to prepare for Dallas."