As a reference, the 65 tooth rear pully will give you overall higher gearing for better freeway performance - it will run at a relatively faster speed (MPH) in each gear at a given engine RPM - higher top speed performance, and potentially better highway gas mileage.
On the other hand, the 76 tooth rear pully will give you overall lower gearing - it will have more low end torque and get off the line quicker - it will run at a relatively slower speed (MPH) in each gear at a given engine RPM. It will get lower highway gas mileage as in top gear the engine will be running at a higher RPM to achieve a given speed.
