I used Rustoleum rusty metal primer for just about all of it so far. Lots of sanding, wipe it down with degreaser, and spray. So far it's working well. Used that under the hood, too, then satin black for the top coat. Had to replace a partial rear frame rail on one side and both quarters are shot. One is about 50% bondo so both of them have to go. Other than that it's a pretty solid car.