In article >, says...
> POR 15 is excellent stuff and so is Good Stuff, but if you are experiencing
> bubbled up rust then it is already too late. as the metal has already been
> eaten through. At that point, best to sand down the affected area , removing
> all rust then use POR 15 or naval jelly to kill any remaining surface rust.
> As there are bubbles, this most likely means that there will be holes left
> where you sanded down the bubbled up rust. If there are holes, you will need
> to bondo them in and sand the surface smooth again before priming and
> painting the surface to match.
>
> There are lots of good how-tos and tips for how to repair rusted thru panels
> if you search Google.
>
> marx404

Its a 10 year old Saturn, not a 69 Camaro. Its not worth that kind of
effort. Just stop whats there and get a few more years out of it...