[R.A.D]

kabwe is right epoxy primer over bare metal. then filler work. and in reality every time you sand though to bare metal you should re epoxy. its like a sandwich. and the best repair and protection for the metal. just regular primer is like a sponge it absorbes moisture. ever see rust bleeding through a car that has just primer on it. it takes longer but thats how to make your work last. and epoxy primer is all i use for sealer before i paint. been doing this profssionally for 30 years never had a come back problem

GOT BAM!