just finished up swapping 3.23 in and 2.94 gears out in the van in prep for a Smokey Mountain road trip pulling my bike on a small trailer. Up with some power down with my MPG I'm afraid.
Not really a very big change, hopefully your mileage wont suffer too much.
I've been thinking of swapping the other way, I do a lot of highway driving, considering the 2.94, but may try out the 2.76 I have setting in the garage.