2.76 vs 2.94 gearing

Hi,how much difference (if any) would I see in performance and mileage switching from a 7 1/4" with 2.94 rear to one with 2.76 gears? This is in a 68 dart with 273 and torqueflite . Not doing this because I want to,but because there's something wrong with the original rear end. Anybody who's experienced both I'd be interested in hearing your opinions. This is obviously not a hot rod,just a daily driver being driven as Chrysler intended jt to be. I'm thinking the difference would be negligible,but I've been happy with the 2.94 gears
I have experience with the opposite. My '79 Aspen wagon had 2.71 gears and I needed the axle rebuilt and couldn't tie the car up while it was being done. So I popped a 2.94 in it while the rebuilt was being done. I lost about 2-3mpg in fuel economy and saw a very slight increase in off the line acceleration - with a A999 deep gear set T/F and a lockup torque converter. So, you need to decide what your priorities are. My focus is my wallet. The less I spend to run the car, the better I like it. 27.5mpg on the highway is better than 24.