I ordered 8 when I did my shield and only used 4. I kept the others for the ones that will strip the next time I had the thing off. While I was in there, I replaced a couple of burnt out dash lights. I also replaced one burned out headlight with Sylvania SilverStars. Best thing I have ever done. I liked them so much, I went down and bought the replacements for the spots in the pods.

The IS can handle the extra wattage because the headlights are operated through a relay, the spots in the pods as well. (or at least my pods lights were)
I also used antisieze on all of those screws when I put them back in, along with small rubber o-rings on the outside of the speaker covers to keep the screws from backing out AND quiet them down a bit.
Glad to be of help.
Hay

Jimmyt