does it sit on the upper black bumper cover or does it replace the black bumper cover?
How many pcs total are needed?

 

this depends on which SS bumper you get. The stock one will just go over the bumper you have now- you will only have to remove the lower valence. It will be held on by overpriced supporting brackets, screws through the end of the stock bumper, and the fron license plate bracket. The air ducts are removable, so there is some hardware associated with that as well.

I think Sickboy has done this complete swap using GM parts. I personally think this is a waste of money to buy all GM parts when the aftermarket alternatives are so much less expensive.

There is a fiberglass replica which I have seen on ebay which looks perfect.

I will try to find pics.