What is the PTO horsepower difference between the John Deere 6M 165 and 6R 165?

The John Deere 6M 165 has a PTO horsepower of 125 hp and the John Deere 6R 165 has a PTO horsepower of 129 hp, a difference of 4 hp. The John Deere 6R 165 has the higher PTO horsepower.