The Dubliner is hoping to bring the Edinburgh club's 110 year wait for cup glory to an end and is already preparing for next season
Fenlon (43), who won five League of Ireland titles and one FAI Cup during his managerial career back home, told the Sunday Independent he is relishing his new challenge with Hibs in Scotland.
"It's incredible just to get to the final," he said.
"When I joined Hibs in November, this was the only trophy they still had a chance of winning, so leading my team out at Hampden is the stuff you dream about, even if I dreamed about a different green jersey. It will take a lot of sinking in on the day."
The former Shelbourne, Derry City and Bohemians manager took over at Easter Road last November and despite a difficult start he kept Hibs in the Scottish Premier League. Leading the Edinburgh club to the cup final has been the highlight of his tenure but he says they are 'underdogs' for the clash with local rivals Hearts.
"It's 110 years since Hibs won the cup. It's incredible to think that such a big club hasn't won it in all that time while other lesser clubs have, and then throw in meeting Hearts in the final and it's madness here. It's crazy, the last time they won it they had an Irish manager, so the hype has been manic," said Fenlon.
He added: "We haven't beaten Hearts in three years and that needs to change. The cup final would be a great place to start."
The Finglas native is bringing his Hibernian team to Dublin for a three-day break ahead of next week's final and paid tribute to fellow Dubliner Matt Doherty who he brought to the club on loan from Wolves in January.
"Matt (Doherty) has a bigger future than Hibs. I pestered Mick McCarthy about him and it's worked out well for Matt, because he's played a lot of football, and for us. I would like to keep him, but Wolves have a new manager coming in who will want to take a look at him, but you never know," he said of the former Bohemians player.
Winning the Scottish cup would give Fenlon the chance to pit his wits in Europe where he has plenty of experience from his time with Bohemians and Shelbourne in particular. He led Shels to the Uefa Champions League third qualifying round back in 2004 only to be defeated by Deportivo La Coruna.
"If we could win and get to Europe that would help the finances and also help to attract players. The fact that I'm used to Europe, it would be great to get back, even if we finished second last in the league.
"To win (the final), we're going to have to play really well. We're underdogs, but that can play on people's minds when they are expected to win," he added.