Jim,
George Cushing's comment is a good one.
Or just use oil base enamel spray or brush on paint. Clean any residual grease and oil of with alcohol.?
Rust-oleum has hammer-tone finishes in spray if you like that and need to cover a large area.
If you just have small spots either get brush on paint and an automotive dauber (micro-brush) or a small Testors nylon brush.
If using spray paint, spray a little into a (disposable) plastic cup or the cap of the spray can and use that.
Mark Christensen