Blend door actuator there is clicking behind my dash?

I have a 2011 fx-2 sport eco-boost. There is clicking behind my dash somewhere. I have dual zone climate control I believe. I see the part is cheap but depending on which one it is it can be very difficult to get to. Can you maybe point me in the right direction? So, when I’m running the A/C the driver’s side seems to stay cold while the passenger side fluctuated between cold and hot air. Any advice would help.