98 Ranger 3L 2WD

First off I would like to say that every single time I come on this website now I forever think of RonD and what a huge loss it is to the Ranger community as a whole because that dude's knowledge on rangers blew my mind and he was always so quick to answer everybody and help them out and he never asked anything for himself. So I recently replaced like my entire brake system and I did so because there was fluid coming down the front of my brake booster which also had a vacuum leak and I originally had thought the leak was coming from the back of the master cylinder. Fast forward 30 days and three Master cylinders and two brake boosters later and I have discovered that my never-ending brake League is actually coming from where the, (I've seen and heard so many different names for this part) we'll call it the s proportioning valve for now, meets with the M/C. Now because I got my new master cylinders at AutoZone and their stuff is **** anyway I didn't also receive what seems to be a super exclusive super hard to get o-ring. It's the one that goes on the front of the proportioning valve that either goes inside of the port or wedges in between the master cylinder proportioning valve. I have tried about seven different size o-rings and if I go with one small enough to go into the port it's still leaks, and if I go with one big enough to meet up between the proportioning valve in the master cylinder it's still leaks. I've tried cranking it down so tight that the rubber completely disappears and it's a metal on metal connection and I've also read that you can't crank it down that hard or delete so I've crank it down less and it's still, and it's still leaks, and it still leaks, and no matter what I do, you guessed it still leaks. As far as I can tell the exact proportioning valve that came with these trucks no longer exist and is definitely not in production anymore and pretty much impossible to find. I don't think I need a new one I just need someone that knows what they're talking about to tell me why I can't get it to stop leaking from there and how to do so without replacing it with one of these adjustable aftermarket weird proportioning valve to everyone seems to insist on putting on their truck. I also keep getting a ABS light on for some reason. I've also read the Ford master cylinder bleeding procedure and it only talks about bleeding at the four tires, I've also had people tell me you have to bleed the master cylinder itself from the bleeder screw and that you're supposed to crack open the lines one at a time on the ABS module and try and bleed that as well. There's a lot of misinformation out there and I'm just trying to get the correct information if anyone of you has it or knows it. Until I get some decent responses on here I'm just going to keep desperately trying weird o-rings and other things. My one neighbor is a mechanic for the city of Philadelphia and he told me if I just take a piece of cardboard and cut it to go in between the proportioning valve and the master cylinder that that will work I've yet to try it but this dude usually pretty spot-on with his stuff