Sir Alex Ferguson was a loyal friend of the army of Manchester United Supporters' Clubs in Northern Ireland and fans are still coming to terms with his exit from the Old Trafford hotseat.
"On a personal note I want to thank him for coming into our lives and visiting my home in Carryduff, allowing me to a co-ordinator for his mum's charity along with my good friend John White," said Dempsey.
"For allowing us access to his players who have also visited our homes and helped us raise lots of money, raise the profile of our Carryduff Manchester United supporters club and increase the support for United in Northern Ireland.
"We at Carryduff are honoured that he sent the best ever United team to these shores to help us organise and celebrate Harry Gregg's long awaited Testimonial.
"I say thank you Sir Alex for getting us to 20 major league titles, thank you for your contribution of 13 Premier League titles and five FA Cups, four league cups, two Champions League titles and a few other trophies besides.
"I'm absolutely gutted but I don't worry for the future. I don't believe he has gone away. I believe he will let his successor get on with it but he will keep him on his toes with his sheer presence and accomplishments.
"I think David Moyes can be just as successful as Fergie was.
"United breeds success and will accept nothing less. Hopefully Sir Alex will remind the board, should the need arise, that he needed a few years to get his toe in. I don't believe Moyes will need that long. I think their mutual respect and friendship will make them a formidable partnership between manager and the Board."