Brake pressure 2 step switch help needed

[KURT GROSS]

I am trying to run my 2 step via an adjustable fluid pressure switch mounted in the front brake line. It is the first thing in line from the master cylinder, before the adjustable proportioning valve and line lock solenoid. The switch states it is adjustable from 250 - 1000 psi. I have installed pressure guages at the RF caliper and the RR caliper to set the proportioning valve front/rear bias and looking at the front guage i am getting 600psi to the front caliper. I can adjust the brake pressure switch all the way to either end of its adjustable limit and still not get it to activate. Two things i am curious if i am doing incorrectly:

1 - I have the pressure switch mounted vertically in a brass tee. Line comes from master cylinder in one side of tee, switch is mounted vertically in the top port, the line comes out of other side headed for proportioning valve. Does the pressure switch needs to be mounted at least horizontally if not upside down due to needing to make sure there is no air trapped in the switch. There is no way to bleed the switch itself and i am thinking maybe i have air trapped inside and therefore not letting it activate whatever plunger that must be inside this thing.
2 - Wiring. These switches come with three wires. Black, Red and a third color. I have two different brand switches, one has the third wire as blue and the other has as green. Does this need to be grounded? I would not think so. I wired in a blue LED light in the dash to show when the pressure switch is activated. I originally had black to ground, red to 12 volt, and the third wire going to launch on my MSD 7AL3, which actually teed to the blue LED also. I can jump 12 volt to the launch terminal on the 7AL3 and the blue LED will come on so i know the light is working.

I am thinking i need to mount the pressure switch sideways or upside down to make sure there is no air trapped but not positive that is the problem. I dont think it needs to be grounded either??

Any help would be much appreciated, Thank you!

Kurt