I am trying to decide the most economical approach to allow my TR6 to be more adaptable to freeway cruising. With my current non OD 4 speed, 2:05X65-15 tires, and 3.7 gear ratio, 70 MPH will be at about 3250RPM. I am considering using the euro 3.45 gear set to lower this. With the torque of the motor I have no concerns about lower gear performance. I would like to be able to cruise at 75 MPH without exceeding 3,000 RPM. I welcome and appreciate any feedback, or suggestions. Thanks in advance.