I cant quite tell from the picture, but do you have noticable rake? Do you think you have any more room to go taller in the back? Can you post a photo from straight on the side and the back?
I do have a slight rake and I will try to capture it in the pictures. Parking on a hill and positioning the camera low makes it look like more than it really is. I don't have much room for taller tires (70 series instead of 60's?). With 255's the tire is pretty close to the front of the fender opening.