On my OWN house which is all stone except the back which is redwood(built in 1924) I have nail head rusting. I spent days a couple years ago counter sinking the nails, priming the nail heads with Kilz,(I think),spackling(exterior),sanding and painting. Of course the nail heads are coming back out and rusting. What do I need to put on the nail heads to lock down the rust? Rustolium? My old mind is drawing a blank and the wife is none to happy either. Thanks.