Paint and primer help

So I dig up my old thread while I work on my Magnum. I'm doing some quick rust repair. And of course, one thing leads to another. So I'm having at it before the weather turns. OH! I'm working on it outside. I'm down to the bare metal and have gotten some flash like type rust.

Is the POR-15 Metal ready ok to use? OR......

I have OMNI Epoxy Primer MP171 for use.