You should not need to strip your paint all off to bare metal. Just make sure edges are well feather edged and you can use an acid primer on those areas, then you can use a high build primer over everything. Then you sand out any minor imperfections and you'll probably want some type of topcoat paint with a hardener in it at least since your offroading so it won't scratch as easily. Like your cat washing post!!! You'll probably get 50 other recommendation for paint this project, everyone has their own methods that work best for them.
