Ancelotti admitted that the tournament had been seen as a distraction to European clubs in the past but insisted his side would not fall into the same trap in Yokohama.
"I think it's true this was not the most important of competitions for European teams," he told reporters on Saturday.
"For Milan it is a big deal."
Ancelotti added: "We have a clear idea how to beat Boca but of course I can't tell you what it is. We are very confident and highly motivated."
Victory over Boca could also help salvage Ancelotti's job with Milan struggling in Italy's Serie A and Jose Mourinho tipped to take over at the end of the season.
A repeat of the mess Liverpool and Barcelona made in the finals of the first two versions of the revamped tournament in 2005 and 2006 could cost Ancelotti dearly.
"Those defeats for Liverpool and Barcelona were a good lesson," he said. "South American teams have taken the tournament more seriously but our aim is to take the trophy home."
European champions Milan arrived in Japan on Dec. 6, giving them far more time to acclimatise than either Liverpool or Barca before them.
"We've had enough time to prepare," said Ancelotti, whose side beat Japan's Urawa Reds 1-0 in the semi-finals.
"We've also overcome the jet-lag.
"The players will approach the game in good physical condition so extra time or penalties will be no problem for us."
Milan lost to the Argentine side in a penalty shootout in 2003 in the tournament's previous incarnation -- a one-off game between the champions of Europe and South America.
Ancelotti is expecting an even tougher game on Sunday from a Boca side who failed to impress in beating Tunisia's Etoile Sahel 1-0 in the tournament's first semi-final on Wednesday.
"Boca's team has a nice blend of young players and experience," he said.
"They're an even better team than they were four years ago. They're very attacking and physically strong.
"The key will be whose midfield quality shines through tomorrow."