Taylor...
As with most things, there is no silver bullet in the paint department. I personally like Rust-Oleum primer on rusted iron and steel parts. Of course, the parts have to be wire-brushed to get rid of flakes and miscellaneous crap. But then, the primer bonds with the rust, which is already chemically bonded to the underlying metal. You simply cannot get a tighter underlying surface for whatever paint you choose. I disagree totally with the notion that you should grind down to bare metal. That does not provide a good surface for painting, and will almost certainly get fingerprints and other oil stains, which will compromise the integrity of the undercoat.
While I've got your attention, now that Memorial Day is over, what are my chances of getting a ride to the SV? I don't own a car, get around on Tri-Met and MAX. If I can visit the railroad, I'd want to stay in a nearby motel. Comments?
Bob Keller