Yup, don't worry about that bolt. It should be removed and thrown away
If it wasn't
for the weight, I was going to order those rims. I believe these are 3 lbs more than mine but I gotta admit they are the BEST looking winter rims offered by Tirerack for the 370Z. I really wanted to see how they look on a real 370z and I was right " VERY good" . Enjoy.
As for snow, you WILL be able to drive it pretty easy. I have driven in snow and frozen snow(thick ice). These tires are pretty awesome. Probably best investment I did for the Z.