JB Weld epoxy is good for small holes, but for the larger ones, you will want to get good at using silver solder. Epoxy in large rust holes will just pop out -- not so with silver solder. You still need to get the rusty tag really super clean with Evaporust first -- and you will also need to get a dremel and be good with that too. Lots of shaping will need to be done to get it to look really good.