With 9,000 Leeds fans headed for Old Trafford, Sunday’s FA Cupthird round game against record 11-time winner Manchester Unitedwill be a throwback to some of the great showdowns between the twoteams.These days, however, Leeds is 43 places behind United down inthe third tier of English football’s pyramid and a victory will beconsidered a major upset.Back in the 1960s, Man United vs. Leeds would mean a meetingof the Charlton brothers – United’s Bobby and Leeds’ Jack. Itpitted United’s George Best and Dennis Law against Leeds’ BillyBremner and John Giles.Moving on to the early ’90s, when Leeds last won the leaguetitle, it was United’s Mark Hughes against Leeds’ Lee Chapman.And 10 years ago when Leeds was riding high at the top of thePremier League at the halfway stage, it was Dwight Yorke and DavidBeckham against Rio Ferdinand and Jimmy Floyd Hasselbaink.That was when Leeds had a team capable of competing for thebig titles – also reaching the semifinal of the Champions League in2001. Soon after that the team ran into serious financial troubleand dropped two divisions while Man United added to its huge totalof titles.United manager Alex Ferguson says his team still has to bewary of a Leeds side which tops the…