[A Cobra guy]

I have an E.M. with the Lincoln MK8 IRS. The wheels are 15" 5 bolt with Goodyears. The 1st season the tires rubbed exactly where Tom said, just behind the seats. This was the inside sidewall during cornering. In my case a 1/8" spacer did the trick. In your case I don't think spacers are an option if you get the offset wrong.

You may not get to lower the car unless you go with narrower rubber. With the spacers I would say the tires are in as far as they can go. They are barely covered by the lip of the fender. I can fit my fingers between the tire and body but not the palm of my hand. I am happy with the look of the ride hight but realy doubt I could lower the car much if any. It has yet to rub with this setup even while autocrossing.
I'm not sure if any of my pictures show this rear ride hight but you could check.

Good luck.

Harvey R.