Depending on what you are shooting you might not even need a head for your monopod. Your Kirk L-Bracket has a 1/4"-20 threaded hole that you can screw the monopod directly into. You can also buy a Kirk Arca-Swiss clamp and attach it to the monopod. Then quickly mount your camera into the clamp in either landscape orientation or portrait orientation. Another option is to move your Markins Q20 back and fourth between your tripod and monopod. It only takes a few minutes. I have a Markins Q3 on one monopod and a Kirk A/S clamp on the other. Good Luck and Enjoy your Nikons!