DUDE...pack it in.
It's obvious you are in way over your head, you have replaced every cooling system item and started numerous posts with no end in sight.
Take my advice, stop throwing money at it, tuck your tail between your legs
and bring it to a mechanic(we ALL do it at some point,no shame). Probably won't cost you more than an hour or two of labor to find out the problem.
Good Luck