Just a little tidbit about the front/rear distribution we touched on earlier. I just put my 370Z up on the corner scales today just for fun. The car had a little over a half tank of gas, no driver, and the spare tire and tools were still in the back. To add to it, the SPL Pro Rear Camber arms I installed added 3 lbs. to the rear, and the Berk Technology High Flow Cats installed removed 10 lbs. from the front. Needless to say, the following percentages are better balanced than your car was completely stock with all of that weight removed out of the back.
My car had a weight bias front to rear of 54.7% front and 45.3% rear.
Point of this is that before removing any more weight from the rear, I would really focus on removing weight from the front, or moving weight from front to back via battery relocation, etc. I know I have touched on this subject already, but now we have a little technical data to back it up a bit.
