Re: How set are you on painting them?
Well on my 280zx i converted my window trim from chrome to black. Looks great. I sanded the chrome off, started with a 100 grit, then went to a 180 grit, then finished with a 240 grit. Then I primed it, Pained it with a rust paint (2 coats), then took enamel paint (2 coats), the finished up with 2 coats of clear coat. Worked great, now for the test of time. But in you situation its bumper chrome so it may be harder to get off and down the the bar metal like I did. Hope this helps.
-Emir