I picked up a used black h3 grill on craigslist a while back that bad a bunch of chips in it. I ended up sanding it down and repainting it. I used a couple spray cans of gloss black enamel. I finished off by wetsanding from 800-2000 grit then using polishing compound to bring back the gloss shine. It was tedious wetsanding it and polishing out the orange peel but the end result was nice. So far it has held up nicely over the past 3 months.

Another option you might consider if you just want an easy way to paint your chrome grille black is to use plastidip $6 a can at home depot. Just spray on about 4+ coats (make sure you clean the grille really well. If you get tired of the black or get ready to return the vehicle you can just peel the plastidip off.

I just plastidipped my rims over the weekend, only time will tell how durable the finish will last. Check out youtube for how-to videos on plastidipping rims.

I have attached some images of my grill, sanded down -> finished product.

 

I have a black 2006 w/chrome grill. I painted the grill black using spreay-on Rustoleum bedliner about summer of '06. I prepped it by sanding it half-***, and then painted on the bedliner.

In the 5 years since then, I've painted it 3 times and it's due for a re-paint. There is very little peeling, however I did get rock chips a lot, which would show up bright chrome against the black grill. I've also had it get chipped off going through a lot of overgrown trails.

Looking back, the only thing I would have done differently is sand it better and use a plastic primer. But I honestly don't know if that would have made a huge difference, I've got tons of paint and it still chips right through, not sure primer and sanding would have helped.

With a white paint job, chrome chips wouldn't show up as much.

So I've spend maybe $30 on paint over 5 years, about 30 minutes per time to repaint...or $300 for a new grill. Easy decision for me

 

*** UPDATE ***
I've ordered the birch white grille (19156164) from 2 sites - hummerparts online and hummerpeopleonline and both orders have been dropped.
It seems that these sites link you to a dealership who then places the order.
The problem is that this part has been discontinued.
I received a phone call about 2 days after my first order and a guy gave me this info he also added that the $65 shipping fee was misquoted and to add at least another $60 to that...
I've scoured the net and have not been able to find anyone with the white grill on the shelf.
If anyone more savy than myself is able to find one please let me know the site.
As for now it looks as though I may have to continue my search for a paint job.

 

If you want, I can check with the Chevrolet dealer were we order parts from at work (were I have purchased 99% of my GM Accessories or parts from for the Hummer). I am positive they can track you one down if there is one left out there. They have been know to make miracles happen

 

Sure - PM me if you find out anything.
Thanks.

 

Im gunna clean mine up sand it down give it some black coats then clear coat the hell out of it.

 

My H3 has a factory painted grill,it has held up great !