I replaced half the floor under an old unibody and sandblasted the rest, so all bare metal underneath the floor, what would be the best primer and top coat for both sides of the floor? There are lap and butt welds I’d like to protect. I’ve read that to prep for epoxy I need to apply a conditioner and then a conversion and remove both with water. Since those aren’t needed with self etching I’m leaning towards the self etching primer but then what over that? Epoxy? Or enamel or what. Thanks

Kind of sounds like you might have been told/read about using a rust convertor. You don't want to do that. Epoxy can go over any well cleaned raw metal surface Epoxy cuts off the oxygen which is needed to make rust. Self etch is old tech to me....I use epoxy for just about anything.

Thanks, the book I’ve got is 3 years old, a text book with 990 pages, but not always clear. It mentions conversion without saying “rust” conversion, as a “anticorrosion” procedure. I wouldn’t use rust converter on bare metal, as I’ve read a lot of praise for epoxy on bare metal. I have some grey epoxy for the underbody now.