iam not 100% sure. but last i knew he was mini biking the motor. if so i would think short shaft as no pto no more. look back u will see frame... but again last i knew. as of todays date and time. lol no clue ..IMO you'd want to use the third one with the longer output shaft, I'm not sure you could run a PTO on the ones with the shorter output shafts. Then again, perhaps you can? This is where my experience is lacking. I don't know the difference in a Quiet line.