May I ask what you are trying to accomplish by not plumbing it between the M/C and the PDSwitch.. You do know the switch is self centering (not like some other brands),, so the lite goes out when the button is released..??
My thought for installing it after the differential valve was to not create an imbalance which would cause the lamp to illuminate. I wasn't sure if this valve would re-center after creating the pressure differential.
I'm warming up to the idea of installing it in the rear brake circuit. I like the idea of it being the same as a "brake torque" without having a line-lock. In other words, using the brake pedal to control the roll-out.
Since this is the case, putting it in the rear brakes line would require that it be installed with the flow direction reversed. (so it wouldn't allow fluid into the rears while holding the fronts on)
