I just did it to mine... I took a grinder and put on a sanding wheel and took out all of the rust. Down to the bare metal and in some place all the way through which left some big holes.. If you the holes are not to big, go with bondo and patch it up nice.... Sand it down and get it painted. If its to big then you may have to get a welder to put some pieces in!! Took me 3 days to get it completed... not so hard..