Honestly cant say as I dont know the no# of the parts, but I can tell you that that two sensors in the pic' are water temperature sensors and the two pin one is for ecu, so if you are having gauge problems and you want to change sensor it is the single terminal one
I would tell nissan parts dep't that you want sensor for gauge and if they fxxx it up, you say thats not what i asked you for!!!
hope i helped (slightly)
Stu.