Rear End Gears

If the 3.23s are in t I'd run those and see how it feels. If it's good to go, you got lucky. If it's a little tiny bit off you can always switch to the 3:55 at any time and if it is way off, then you know you will need to get into the 3.91 or 4.10 range. All of the facts and figures are great but there's nothing better than the seat of the pants and the computer directly above our shoulders to determine which gear ratio we want.