has anybody changed the gearing on their rearend? if so, what did you change to, what else did you have to change (computer flash, speedo calibration, etc), mpg change, and are you happy with it. trying to get a little more out of it off the line but i don't want a drastic change to the top end rpm. also, did you have to change the shift points for the trans, assuming you have an auto.

thanks