He told the Echo
"It's an achievement I am proud of and it's unbelievable that my 400th appearance should fall on such a special day," said skipper Kavanagh, who would collect the trophy if City win.
"When we played Bristol City in the semi-final I saw that Neil Alexander was making his 100th appearance for Cardiff and Robert Earnshaw his 150th.
"They were milestones for both players and they made the most of them by helping Cardiff City reach the final. It will make it an unforgettable day if we can clinch promotion on Sunday - a day I would be able to look back on in years to come.
"If we can beat Queens Park Rangers it will be my best summer ever, but we haven't achieved anything yet and every player knows there is a major task to be completed.
"There is a great feeling of togetherness in the squad and we are capable of achieving our goal. None of us will ever forget the sickening feeling of failing in the play-off semi-finals last season.
"That will spur us to greater heights in Sunday's final.
"It was horrible missing out on automatic promotion and going into the play-offs, but there would be no better day than going up in front of our own fans at the Millennium Stadium. It's going to be a tough match and we will have to play well."