The line lock should be after the Proportion Valve. I know this from experience, it will not lock the front brakes and on burn out the car will roll forward.
This is the correct way to run your brake lines with a line lock and proportion valve.
1] disconnect both front brake lines from proportioning valve
2] install a pipe plug into one of the holes were either of the front brake lines was hooked up to
3] install/route a line from the remaining open port on the proportioning valve to the solenoid "in" on the line lock
4]install/route a line from the solenoid "out" of the line lock to a T-fitting "unless your Solenoid has 2 line outputs"
5] at the T-fitting "or solenoid that has 2 line outputs"-- install /tighten the two front brake lines
__________________
