Thanks everyone. You all said it is necessary to cut out the rust. Will do. I liked the idea of boxing it when I am done to give additional strength. I was suprised that no one said to make vertical cuts and cut out a section. I really didn't want to do that and I am happy no one advocated doing it! It is a 3/4 ton so I will mike the thickness and look for the necessary steel. Thanks
Rick in VA