Blucuda413, In most cases the distribution blocks on Mopars is a differential pressure switch. If it has a wire going to it, it is a differential pressure switch. If you plumb it like you say with a "T", then the solenoid can go wherever it fits.

I planned on leaving a differential pressure switch in my car, because it will see 10% street duty, so the warning light might be handy.

I disassembled the differential pressure switch in my car to try and figure out how much volume shifts when the line lock is used, and the rear circuit pressure goes to zero. But, amazingly, after forty one years, the piston is froze in the bore, so I cannot get it apart to figure it out.

Thanks again, John