What one has to remember is that, on the full sized unlimited, the rear wing is only used to fine tune the boat's ride. Everything else is done with the boat's hull design, props and internal systems placement.
To illustrate my point, I only have to go back to the 1970 and 1973 Pay'N Pak hulls.
During the 1970 season, the first of the boats ran with two Chrysler big block engines, connected in series, driving the prop. Since the engines were relatively light, there wasn't much weight in the hull. The engines were, however, unable to get the boat up to the speeds needed to be a consistent contender due to lack of power and reliability issues. It was, however, a fairly stable hull, considering it was a new design.
Prior to the 1971 season, the boat was refitted with a Merlin, much heavier than the Chryslers, and the hull was rearranged internally. The boat was faster but unstable due to the weight distribution. It wasn't until 1973, when it ran as the Budweiser, that the boat was tamed down and became a true competitor. The only boat to beat it was the brand new Pay'N Pak, a boat that was also very light due to it's construction as well as highly unstable. It was such a challenge to drive that only three men were able to win with it consistently:
Mickey Remund
George Henley
Bill Muncey
The only other driver to ever win with the 73 Pak hull was Ron Snyder. He scored one victory with the boat in the early 80s, running with a methanol powered turbo Allison. The engine was heavier and also required twice the fuel load when compared to when the boat ran the Merlin, making the boat much heavier than when Remund, Henley and Muncey drove it to four consecutive national championships. The added weight tamed the boat's ride but newer boats were able to beat it due to newer and better designs