Line Lock Install

I just installed a line lock that will not lock the front tires. I have the
outlet of the master cylinder going to the inlet of the line lock.The outlet
of the line lock to the inlet of the proportioning valve that feeds the front
brakes. I hold the brake pedal down, hit the switch, let off the brakes and
front brakes will not hold. The solenoid valve is good and I have checked
power to the valve. Do I need to tee into the front brakes after the pro-
portioning valve? The car is a 72 Demon with kelsey-hayes manual brakes.
I appreciate your input to properly install this.