As fas as treating rust I use Zero Rust, I have had excellent results with it. I have parts of my 90' that have been exposed to the harsh New England climate for two years and no return of rust. It does not have to be top coated, it comes in colors, I used black, its a cross between a flat and satin finish, has not faded at all. I also have used red and clear coated it, still looks great.
Price varies between $19 and $25 a quart, keep an eye out for JC Whitney, they periodically will have it on sale for $12 a quart. Good time to stock up.
The best thing, IMHO, about it is that it does not contain isocyanates, POR15 and the one mentioned above do. Isocyanates can kill your lungs unless wearing approved breathing gear.
As far as the rockers you can do as above or if you want the stock look, get replacemanet rockers, JC Whitney does have ones that can be welded, riveted or screwed on over the old ones. They fit real well, if you take your time. You can still cut out the rust, and cut these to fit in the area you removed and weld them in.
