Sorry, I just have to say, this is a BAD idea. They have height requirements on rides for a reason. Granted they do normally err on the side of caution when determining them, but don't you want that when it concerns the safety of your child? Even if it were just an inch or two and not 7 inches, it would still not be a good idea. Very recently a 3 year old girl was thrown from a ride for which she was deemed tall enough, she slipped under the lap bar and was thrown from 8 feet in the air. Thankfully she wasn't seriously injured, but I'm not willing to risk even a mild concussion for my kid just to get them on a theme park ride.
http://abcnews.go.com/blogs/headlin...l-thrown-from-carnival-ride-at-houston-rodeo/
This may have been a joke, but just for people who might think this is a possibility to get their kid on that ride that he really wants to enjoy, it's not worth the risk. Make another trip when your kid is taller.