Try going back up to 7k oil in the center diff. My cars (including the 8ight) have always felt "floaty" to me with lighter oil in the center. 2 and 3k in the rear should make for more of a posi-traction effect on throttle. If you go higher in the rear diff the car will be a little less locked in on high speed sweepers/high speed turns. 5k/7k/2k is perfect in an 8ight and 56 pistons with 25 or 27.5 oil in the rear shocks also helped stability a lot when I ran that car.