Rebinding mouse buttons to Xbox 360 trigger

[Zonular]

Im trying to rebind my left mouse button to the right trigger on my xbox 360 controller which is plugged in to the pc. From my understanding, when the right trigger is pressed down, the Z value changes from 50 to 0 and back to 50 when released. Is there any way to modify the value without pressing the actual trigger button on the controller and make a bind out of it?