Sheet metal is sheet metal, doesn't matter if its a hood or oil pan. Treat it as any other body panel. 220 sanding, primer, paint. If it comes off, then something wasn't clean.
Extra cleaning is the only difference, use a good quality prep cleaner or wax and grease remover. From there its standard painting.
Heat has nothing to do with paint coming off, it will change colors and bubble if really hot, but still won't flake off.
I painted a Stanley Steamer hood that regularly sees fire all day long and after 15 years needed some touch work.
Joe
