what gears to get

4.10's will make the biggest difference, but will tach higher if your doing alot of highway driving. If you do alot of city, and a little highway driving id say 4.10's. If you always gonna be running highway and doing alot of higher speed interstate travel id go 3.73's.

Either one is gonna be a jump over stock. I think generally most people say 4.10's tach about 200rpm higher than 3.73's do (I think, not positive).

I have a buddy that put 4.30's in his auto and its insane.
 
well about 2 mins ago i just bought a set of 3.73s and im anxiously awaiting there arrival :D I got the 3.73s cause i do a good amount of highway driving especially making the 250 mile drive home from college like once a month and i think there might be a 2.1 kenne bell in the future :)