Spotlight On City During 50th Anniversary!
Most of the remaining 12 were journalists, who included among their number former Manchester City goalkeeper Frank Swift.
There have been fears the minute's silence in memory of the victims at Sunday's Manchester derby could be disrupted by some City fans.
David Gill (United chief executive): "We've been working closely with City and discussed it with them.
"Frank Swift was one of their greatest goalkeepers and we've talked to them about the plans for the day.
"They're aware of what we're doing, for example with the kit, and they're doing something special with their kit as well. We'll be giving a memento to every fan, both United and City.
"There are 3,000 City fans going through the gate on the day and we're involving some of their former players on the day.
"We're working to ensure they remember that it wasn't just Manchester United, it was the city of Manchester that was affected and it was the world of football that was affected.
"We hope and believe that the minute's silence will be observed appropriately.
"In football, there is always trepidation and it's a very tribal game.
"That's why we've worked on the communication and the explanations so we can honour it appropriately and respect it.
"If you look back and see that 23 people lost their lives, of which eight were footballers in their early 20s by and large...
"It's a true tragedy for football so if you're a football fan, as the fans coming through the gate will be, you should reflect on that and make sure that you behave appropriately."
A memorial service will be conducted by the club chaplain to coincide with the time of crash at 3.04pm.
There will also be a minute's silence at Wednesday's Wembley friendly between England and Switzerland.