Paramount’s “Transformers: Dark of the Moon” illuminated the global box office, with the film expected to collect $372 million through Monday — the third-biggest opening of all time for a comparable six-day release behind “Harry Potter and the Half-Blood Prince” and “Spider-Man 3.”

Domestically, “Dark of the Moon” is projected to make $97.4 million in three days, with a total four-day estimate (including Monday’s Fourth of July holiday) of $116.1 million. Par launched the pic wide on Wednesday (with additional 3D-only screenings Tuesday night) for a U.S. cume through Monday reaching $180.9 million. That’s behind the previous “Transformers” pic, “Revenge of the Fallen,” which tallied $215 million in six days.

But “Dark of the Moon” still managed to beat the previous biggest three-day opening during Fourth of July weekend: “Spider-Man 2’s” $88.2 million debut.

At international wickets, the Par tentpole surpassed its predecessor by 51%, with a cume of $210 million through Monday, including preview screenings. “Dark of the Moon” now stands as the studio’s best-ever overseas opening, beating 2008’s “Indiana Jones and the Crystal Skull,” which posted $147 million overseas.

Imax contributed this weekend an estimated six-day total of $22.5 million for “Dark of the Moon,” the first time the exhib crossed $20 million for a single pic in an opening weekend.

Also opening at Stateside plexes, Tom Hanks-Julia Roberts starrer “Larry Crowne,” being distribbed by Universal, debuted at the high-end of expectations, with three-day estimates tallying $13 million and an estimated $15.6 million in four days.

The weekend’s third wide release, 20th Century Fox’s teen/tween-targeted “Monte Carlo,” took in $7.6 million through Sunday (Fox will release four-day projections on Monday).

Overall domestic totals from Friday to Sunday were up 6% vs. last year’s holiday frame when “The Twilight Saga: Eclipse” bowed. Though with Fourth of July on a Monday this year — the holiday typically isn’t a big moviegoing day — weekend figures through Monday are projected to fall behind 2010 by 4%.

3D saw a much-needed resurgence domestically, with “Dark of the Moon” expected to earn 60% of its opening from the format. (Not surprisingly, however, overseas auds purchased more debut 3D ducats at 70%.)

The flagging format has struggled with U.S. moviegoers in recent months, brought to a new low last weekend by “Cars 2’s” 40% 3D debut share.

Par vice chairman Rob Moore attributed the declining 3D percentages — at least, in part — to the industry’s influx of 3D pics.

“There are so many 3D releases, audiences now are going to pick and choose which films to see in 3D,” Moore said, before adding that the format has become a tool more for event filmmaking. “If the 3D is good, audiences are going to pay for it.”