I need to repaint a part of my radiator. I have already sanded the tarnished area with a grinder and a flapdisk but not the whole area (half of a fin) I'm getting ready to refinish, IOW most of the area still has paint but I removed it where it looked ugly (some burn marks).
Should I use an oil based primer (as I think that's best for metal) over the whole area and then just regular indoor paint?