I got my DD rims, and they went straight on the car no problem. Nothing special required for my 01. However, some tire companies and exhaust companies do things a little different than the other companies, such as Nitto. Their 315s are a tad bit skinnier than, say, a BF Goodrich 315. With that in mind, there might be a combination out there that would have a 315 rubbing a tailpipe, but I haven't heard of it yet. I had a set of 335/35/17s for a while, and they went on with no problem, but were a bit too close to my quad shocks for my liking, so I flipped the quads over, and that solved that. In regards to spacers, if you end up with the size rims you posted, put 275/40/17s up front, and 315/35/17s in rear, and it will look sweet. The tires stick out just far enough to line up with the fenders perfect on my car. Not knowing what year your car is, I can't say for sure what it will look like, but if it's a 99-04, it will definitely be good.
Another SE Michigan stangnetter. You're the third this week I've seen!
