Right. These guys have all been beating around the bush, too polite to give you the straight facts.

Mate, you have two chances of doing what you are talking about: None and f@ck all.

You can't get hired by Qantas (disregarding the fact they're not hiring) because you aren't prepared to go back and do year 12 maths and physics. Yet, you expect to compete with Americans, all of whom will have a four-year university degree and thousands of hours in the Military or the Regionals. Oh, and you don't have citizenship, or the right to work in the US. Then, after you're hired, you expect to move on to one of the most senior aircraft, one on which a guy hired 20 years ago is only a junior F/O, and commute 13 or 14 hours home. Do they not drug test in PNG?

It's a pipe-dream and you're better off focusing on something at least in the realm of possibility.
Cheers, T