[dsmreck]

It really does depend on how bad it is, and that looks pretty bad. The thing about it is there are two layers of metal so u will need to start grinding the top and bottom to see how far it goes and cut out all the rust. Than you would want a sealer and paint inbetween and all around everything that's left after cutting and grinding. Step five would be to fab up a top and bottom layer to be welded into place. One at a time so you can use the sealer inbetween. Than bondo and paint. Ask dark2g questions if you need further help or explainations on rust and how to treat it, he is the man at body work.