With 9,000 fans heading over the Pennines with them, the atmosphere between two bitter rivals will be high octane to say the least.
But the West Yorkshire outfit are aware an FA Cup tie is one thing. The ultimate aim is to make the visit an annual event once more.
And in Ripon-born Grayson, Ferguson believes the Elland Road outfit have the man who can turn that dream into reality.
"They will not be too far away from the Premier League in the next couple of years," said the United boss.
"When you look at the position they are in at the moment in League One, they look certain to be in the Championship next year.
"And with the motivation and drive that is coming from the manager, they have a great chance of going further.
"Simon Grayson is a local boy himself, as well being a former player.
"Some people have targets in life. He has reached his and his team are not letting him down."
Ferguson's view is based on Leeds' unlucky Carling Cup defeat to Liverpool at Elland Road earlier this season, and a League One table that shows the Whites heading a list of strong teams that also includes Norwich, Charlton and Southampton.
But that rounded opinion will not be shared by many United supporters, who will simply want their side to impose superiority on opponents whose struggles have been widely welcomed at the Stretford End.
Ferguson hardly helped relations between the two clubs, first by snaring Rio Ferdinand in a £29.1million deal in 2002 and then bringing in Alan Smith, the ultimate Leeds cult hero who opted for Old Trafford as his home and risked the abuse of the fans who loved him.
"We don't need to spell out what Sunday's game means to the Manchester United fans," admitted Ferguson.
"There have been some fantastically feisty occasions over the years. And there was always a tinge of hostility.
"We always told the players to make sure they behaved properly on the pitch because we didn't need to add to the problems off it.
"Leeds are bringing 9,000 fans, so it will be a busy day for the police.
"But it will be an absolutely brilliant atmosphere and should be a good cup tie as well."
An atmosphere Ferguson admits he misses.
"I used to enjoy the rivalry," he said. "It makes you perform.
"We had some great games at Leeds. The atmosphere was always electric and our record was pretty good."
Indeed, Leeds have not registered a win at Old Trafford since 1981.
That record is unlikely to be challenged this weekend given Manchester City are set to be the ones facing a more youthful United line-up next week in the Carling Cup semi-finals.
At least having the opportunity to test themselves against the likes of Paul Scholes, Ryan Giggs and Wayne Rooney, whose arrival at Old Trafford coincided with Leeds' demise, can be a reminder of better times when the Yorkshire outfit were able to compete on an equal footing.
"The first problem seemed to be financial," said Ferguson of Leeds' demise.
"They had to sell all their best players - and they had quite a few; Mark Viduka, Harry Kewell, Alan Smith, and all the rest.
"But they were all sold on, which is what happens if you are financially restrained.
"And if you sell your best players, you can bet your life that the results will change as well."