I posted this in the technical section too, wasn't sure which place i'd get a better response.

Background:
OK so..I just recently swapped my motor over from a LS to a GSR chassis, did the abs-removal on it. I bought the Integra RS MC, which was part number 46100-ST7-013, bought the 40/40 prop valve, and the four RS front brake lines, and they all fit up perfectly. I wasn't sure about the which brake booster to use, so I just got one from a buddy. Now from what I've been reading lately, you're not supposed to be able to use a non-abs mc on an abs brake booster because i guess they are supposed to have different bolt patterns?, but my LS brake booster looks the exact same as the one that is on my car, and my non-abs mc bolts onto it just fine.

Problem:
Driving was fine at first when i got everything together, and then the pedal slowly started getting stiffer and stiffer, and eventually all four brakes locked up. To get it to release, I ended up bleeding the two front calipers. After that, it drove fine for a while, and then same thing, pedal got stiffer, and they started to lock up.

I know the search function is my friend, i've read about 30 threads on this topic, and i'm pretty sure i couldn't find ONE that actually had a conclusion, with how they fixed the problem. I have tried adjusting the rod going to the mc, and it did nothing. I just bought another brake booster (used of course) that was supposed to have come from an integra RS and looks the exact same as the one that is currently on there. I don't know what to do. We have bled the brakes quite a bit, i'm pretty sure there is no air in the lines, since the pedal doesn't feel spongy at all. I have also read that the master cylinder is supposed to sit flat up against the booster without having any resistance when installing it, weird thing is, mine has about 1/4 inch gap before i feel like i'm actually pushing the mc on. I checked on my old car and it sits flush, so i know something is wrong. Do i just keep getting the wrong brake boosters or what?? Also, idk if this means anything, but after i turn the motor off (and it doesnt matter whether its been 10 seconds or 10 minutes) if i take the hose off of the brake booster, it lets out alot of pressure, is it supposed to do that? Would it be possible that my check valve is on backwards?

Input please!

brake booster i just bought that is supposed to be from integra rs:







And here is how far it sits down onto the brake booster without resistance

 

anybody?