Is there anything else done with the car - mods, replacement parts, etc? Have you tried pulling codes? Not that it might produce any with the car running, but it's not a bad idea to check anyway. How are you measuring fuel pressure?
Those questions out of the way, it could be a few different things. Bad hose somewhere, clogged fuel filter (I realize you said it's been replaced), weak pump, kink in a line, etc. Unfortunately, we probably won't be much help until we know more. And pics are always a good thing, both of the car (because everyone likes to see what we're dealing with ) and of whatever trouble area you may be dealing with (because everyone likes to see what we're dealing with).
I can sense and empathize with your frustration, but so far you've not given us much to work with. And, as @Noobz347 said in his reply to that thread, it will help to use punctuation and more complete sentences to try to eliminate any chances of misinterpretation.