I hope that is enough, you might need less than 6" and don't forget to set the suck (tilt or toe in) and list, on flat ground the plough should lean slightly, you can recreate the lean by make the plough level when the left two tires on are 4" blocks. This simulates two right wheels in a furrow and correct the lean of the tractor to the plough. Brinly has a manual detailing this, but path Norman gave will probably be the easiest to understand.