Ask yourself this question... .what are you going to do when you have two + kids and you can't put both in the middle?
The best place for a car seat is where you get the best install. Its likely your vehicle doesn't support LATCH for the center position, so if you were using it, you were using it wrong this whole time. READ your vehicle manual, most center seating positions do not allow th use of LATCH, you have to use the seat belt to install.
What isn't fitting? The seat doesn't fit there? The base doesn't fit there? Bad install? What exactly isnt' fitting. Because if you can get it on the side, you can surely fit it in the middle. And if you had an infant seat in the middle, you can fit a convertible. For an older child, you don't need it reclined fully. the SEAT needs to be in teh recline position, (per Britax requirements) but you don't need to roll towels for the front to make sure its at a 45degree angle. That angle is for newborns, older kids can be at a more upright position.
www.safekids.org and find a CPST in your area to help you. She's not ready to forward face, there is not one good study or argument for forward facing a child before 35lbs. You have a great seat, so use it to its potential. Install it on the side rear facing until you can find a CPST in your area to help you install it in the center if you choose. But for what its worth, my boys haven't ridden in the center, ever, and I'm very confident in their seating positions.