Habul, a successful Charlotte-based Australian racer and solar entrepreneur, and Engel will also be joined by regular Canadian co-driver Mikael Grenier.
Habul and Grenier are fresh off a seventh-place result in class at Detroit on the Belle Isle street circuit earlier this month.
“Maro has been a part of our team for some time and it is good to have him back this weekend,” said Habul.
“We have made some changes since originally running our spare car at Detroit and believe we will have the speed to be a contender this weekend.”
Watkins Glen's six-hour race is a fixture on the IMSA calendar, taking in the 5.44km (3.4-mile), 11-turn road course in New York State.
While the event has a wealth of history, Habul hasn't raced at ‘The Glen' since 2018 where the squad finished eighth in class.
Watkins Glen has been a happy hunting ground for Australians in the past with Alan Jones winning the US Grand Prix at the venue in his 1980 Formula 1 championship year and Marcos Ambrose winning his first NASCAR event at the track.
“Watkins Glen is one of the world's most iconic race tracks and it is always cool to race there because of its history,” said Habul.
“When you have a look at the record books there have been some Aussies who have made their mark at the track and it would be good to continue that tradition this weekend.”
The Sahlen's Six Hours of The Glen takes place on Sunday at 10:40 local time (Monday at 00:40 AEST).