The Hammers host Leeds still sitting inside the bottom three of the Premier League.
Writing in his match programme notes, Bowen stated: “We’re into April, but there is a lot to play for, both in Sunday’s quarter-final and in the Premier League as well.
“We can really turn what's been an underwhelming season into a really special one in the last seven league games and three potential FA Cup games we’ve still got to play.
“It’s proper business time, with no other breaks between now and the end of the season. It’s good to be back and we’ve been working hard the last few days at Rush Green to be ready to go.
“A Wembley trip for everyone associated with this Club would be incredible. This is the FA Cup, the competition we all grew up watching and dreaming of winning, and a win today would take us to the national stadium, so it’s a big opportunity, a big moment, and one I’m really looking forward to.
“You will all be up for it and will be right behind us and Leeds are going to bring a lot of fans, so it's going to be a good set-up for a great game. Now we just have to go and do it.”