Question: What NBA Finals featured two of the most storied franchises in the NBA who had faced each other six times in the 1960's?

<P0-S0> The Celtics–Lakers rivalry is a National Basketball Association (NBA) rivalry between the Boston Celtics and the Los Angeles Lakers. <P0-S1>  Both the Celtics and the Lakers are the two most storied franchises in the NBA, and the rivalry has been called the best in the NBA. <P0-S2>  The Boston Celtics and the Los Angeles Lakers have met a record 12 times in the NBA Finals, starting with their first Finals meeting in . <P0-S3>  They would both go on to dominate the league in the 1960s and 1980s, facing each other six times in the 1960s, three times in the 1980s, and two times in the late 2000s. <SEP> <P1-S0> The 1978 NBA World Championship Series was the championship round of the National Basketball Association (NBA)'s 1977–78 season, and the culmination of the season's playoffs. <P1-S1>  The series featured the Western Conference champion Seattle SuperSonics against the Eastern Conference champion Washington Bullets. <P1-S2>  The Bullets defeated the SuperSonics in seven games to win the NBA championship. <P1-S3>  Bullets power forward/center Wes Unseld was named MVP of the series. <P1-S4>  Before the Cleveland Cavaliers' Game 7 win at Golden State in the 2016 NBA Finals, this was the last time a road team had won Game 7 in the NBA Finals. <P1-S5>  The 1978 Finals is the only NBA Finals series since the 1958 NBA Finals in which both teams had under 50 wins. <P1-S6>  The 1979 Finals are the only NBA Finals to feature two teams with under 50 wins in an 82-game season. <SEP> <P2-S0> The Lakers–Spurs rivalry is a National Basketball Association (NBA) rivalry between the Los Angeles Lakers and the San Antonio Spurs. <P2-S1>  The rivalry started in the late 1970s and peaked in the late 1990s and early 2000s. <P2-S2>  Since 1999, the teams have met in the NBA Playoffs 7 times, with the clubs combining to appear in seven straight NBA Finals from 1999–2005. <P2-S3>  Additionally, the teams won each NBA Title from 1999–2003 (the Spurs won in 1999 and 2003, while the Lakers won in 2000, 2001, and 2002). <P2-S4>  From 1999–2004, the rivalry was considered as the NBA's best, as each time the clubs faced each other in the playoffs, the winner advanced to the NBA Finals. <P2-S5>  The rivalry fell off from 2005–07, with the Lakers missing the playoffs in 2005 and losing in the first round to the Phoenix Suns in 2006 and 2007, but intensified again in 2008 when they met in the Western Conference Finals, and later on, again in the first round of the 2013 Western Conference playoffs. <SEP> <P3-S0> The 1987 NBA Finals was the championship round of the National Basketball Association (NBA)'s 1986–87 season, and the culmination of the season's playoffs. <P3-S1>  The Western Conference champion Los Angeles Lakers defeated the Eastern Conference and defending NBA champion Boston Celtics 4 games to 2. <P3-S2>  The key moment of the series was Magic Johnson's junior sky hook in Game 4. <P3-S3>  This was the tenth time that the Celtics and Lakers met in the NBA Finals (more than any other Finals matchup). <P3-S4>  It would be the Celtics' last Finals appearance until the two teams met in 2008.