I'm restoring a JD 44 plow that I recently purchased. Primary use will be annual plow day, maybe a small amount of plowing in addition to the plow days, and perhaps displaying at tractor shows. The metal is almost complete rust and I'm disassembling and cleaning the rust using a wire wheel, then wiping with brake parts cleaner. I follow that with a coating of ospho, letting it dry several days, then priming with a self etching primer. The metal is pretty pitted, so I'm not looking for a shiny finish. I've read several pages on this forum and have a better idea of how to proceed, but do have a few questions. I've settled on the Rustoleum tractor and implement paint since I've read it holds up pretty good. I'm spraying the primer but plan to brush the base coat. I tested one small piece this afternoon using a foam brush and to be honest, can't really tell it was brushed. It does look a little lighter shade than a few places I've found green paint such as on the underside of bolts, but I suppose it will do. My main question has to do with adding hardener. I'm aware of the hazards and the need for supply breathing air to be from a different area, but do is the hardener safe to use if I'm brushing? Maybe using a respirator to protect from fumes? Will the Rustoleum paint be hard enough to not really need to worry about using the hardener for the use I'm planning for? It will probably be left outside, so I was wondering if the hardener would help with the paint fading. My default plan is to do the rest of the parts I've got primed without hardener and continue to use a foam brush unless you guys think I need to change coarse. Thanks.