What paint did you use and what steps did you take?
The grill comes apart in basically 3 pieces.
The logo, the chrome frame, and the black mesh.
There are about 6 screws on the backside that hold the chrome and mesh together, along with a bunch of snap together clips.
After removing the screws, I carefully separated the clips.
I used 180 grit sand paper to rough up the chrome surface. This wasnt too difficult. It was just time consuming. It was a tedious task to get in all the little bends and corners.
Then I primered it with self-etching primer. Just regular spray can stuff.
A friend of mine who does auto painting, painted it with Sikkins acrylic/ urethane. Then he cleared it with 3 coats of urethane clear coat.