What is good to use on bare metal when you strip 20+ year old paint.There is minor pitting in some areas and that gets a wire brush attachment on a grinder.Rust outs get cut out. But would you use a rust neutralizer,say on a 2ft. section that shows no rust? I would like to treat every inch with some rust treatment but am not sure of what works and if you then wash it off after it dries? Concern is about whether primers will adhere if its not washed off or sanded,or something done to the rust neutralizer???