Since you are going for the ultra clean look (great choice for such a nice notch)I would go for a neat cowl. Also,
I've actually seen the SVO hood MORE than the stormin norman, being "originial" with a Mustang is a bit of a challenge. As long as it looks nice, shouldn't really matter since its a production car with a huge following and a massive aftermarket anyways
The rims look great, but make sure the gray you choose compliments the polished finish. I've seen some custom grays that look faded and cruddy when set off by shiney wheels. You said you were going with Mineral Gray correct? Judging from the cobras I think that will look fantastic, especially with those ghost flames. Are you going to use Kameleon for the flames? That would look incredible with lots of clear.
Keep us posted, and can't wait to see the finished product!!