Welcome to the forum Andrew, it sounds like you have a really nice Jeep. Very likely it has short arms, long-arm suspensions are pretty rare for a 3" suspension lift height. On the front axle, did someone swap out the factory Dana 30 for a Dana 44? The front Dana 30 can, with its steel lubricant fill hole plug, fool a lot of people into thinking it's a Dana 44 and not the factory Dana 30. Awesome on that Dana 44 in the back, that's where the D44's added strength really pays off.
Not a bad 15th birthday present!