PST Power disc brake help

I purchased the front power disc brake conversion kit from PST Performance a while back.

Ive been trying to get info from them on the master cylinder and they have not been helpful.

I purchased a set of brake lines for a 71 duster with power disc brakes and the fitting that goes on the rear most side of the master cylinder was WRONG.

PST has been unable/unwilling to tell me what size fitting and flare style i need, the car has been undrivable for weeks because it pisses brake fluid at the master cylinder attatchment point. can someone point me in the right direction? I JUST need the rear drop down line that goes from the master cylinder to the distribution block below.