Jorden, just a thought; if at this point you still are having no luck, you may want to replace the rubber hoses of your brake lines (if you haven't already). After many years, these hoses are prone to deteriorate on the inside, like a plugged artery, literally, even though they may "look" o.k. from the out side.
I have replaced many of these. If you disconnect the metal line from the rubber hose, have someone push down on the brake pedal, if you get a full powerful stream out of the metal line, chances are that your problem, besides air, is plugged rubber hoses. Be sure to catch the fluid coming out of the line in something!
Good Luck! Like David said, "from one who knows"
