Myself and my teammate spent about five hours testing (a total of 10 track hours as we have identical cars). We tried 3,000 rear diff and tons of bar and ride height changes, as well as 0s and 1s inserts in front. Taking Ryans advice, we came back to the exact kit setup (with 5,000 rear), with the ONLY change being 0s in the front for a tighter indoor track. Car was MUCH better than anything we tried. Surely the kit setup is there for a reason. We found that a higher rear ride height provided more grip in the slick so we ended up at 26/28 ride height on a slick track, but started at 26/26 or 27/27 on the high-grip tacky track (still testing ride heights, but great thus far). MAKE SURE TO USE TLR OIL AND NOT KIT OIL--CRITICAL!!!
Just our two cents worth of input after a great deal of testing.