I'm picking up my car today from getting 3.73 gears installed and forgot to place an order for a new tune for gears until yesterday morning...hoping I'll have the tune by today but doubtful. But I'm forgetting whether or not you can change ratios when you connect the tuner to the car? Btw it's a Bama tune.
Yes, you can change the ratio with your current tune. You basically have to re-upload your current tune and before pressing continue, edit the axle-ratio when it asks you if you want to make any configurations. Then, you're good to go!