I got the High Country grille today and got it installed. No problems. The end, lower bolts are a bit of a pain to remove from underneath, however, if the upper bumper molding was removed first, the bolts could be gotten to from the front. When I reassembled, I bolted the grille in place and then pressed the upper bumper molding into place.
The older part number is 23173538, while the newer part number is 23473702. The one difference I noted, was the center post, which snaps into the truck frame is absent on the newer P/N. (Pic is from the older P/N)
One of the reasons I wanted to change the grille, was because the snow plow plugs wouldn't fit back through the honeycomb grille. I haven't poked them back through all the way, yet.
Note: I do have the chrome and black honeycomb grille, which i can make available, if you need one.