So just so I have it right in my head. If the rear end ration were changed to a 3.08:1 or a 3.45:1 then the motor would rev higher at highway speed and top speed would be reduced.
also note that there is a ratio applied at the bevel gear output at the other end of the drive shaft....and that also has a big effect on the engine speed vs rolling speed
also note that there is a ratio applied at the bevel gear output at the other end of the drive shaft....and that also has a big effect on the engine speed vs rolling speed