I don't know. I looked at the grilles from underneath a while back, and I don't think it can be removed - you may be able to seperate them to paint them and then reassemble it, but i don't think the honeycomb will mount without the chrome bezel.
The only thing I know of is the throttle by wire difference. I haven't looked into it since it's not my car; it's the wifeys and I can't do anything to it.