Not a King Ranch but I just painted my XLT grille yesterday.
Excellent post, looks nice, thanks.
Like the OP, I also have a KR (2010) and after looking at the way the new 2011 KR grills "Super Duty" section and surrounds look with matching body paint instead of chrome, I have been looking for a way to do this for mine. IMO, there's a bit too much chrome up front, even though my bumper is accent color rather than chrome. Just a personal preference.
I'm probably going to have a custom set of bambi bars made for over my bumper and grill area (lots of big critters on the road in ID), and they're suggesting to paint it in the accent color, so I'd probably also paint at least part of the grill that same Pueblo Gold rather than try to match my White Platinum Tri-coat. I might leave the inside "bars" of the grill chrome, not sure, will "paint shop test" it first.