By stock, are you referring to the alloy rims that came as original equipment with the car? That potentially being the case, you need to determine what the backspace for your rims is. Backspace is the distance from the mounting flange to the outside edge of the rim. The deeper the backspace, alternatively termed the offset (this terms subject to dispute) the closer the wheel comes to touching the inner wheel house. The shallower the backspace, the closer the wheel comes to touching the lip on the fender seam. I have run 205/70R15's on a 15 inch Chevelle style steel rim and not encountered rub or interference. Not sure what is on my fancy alloy rims; parked them in favor of the 15's to get a little extra ground clearance. Seem to recall the that my stockers were only 14 inch. You might be able to look at rims from another vehicle line such as the El Camino or the Camaro for a little help. The Elky might measure out the same but the Camaro rims could be shallower, allowing you to employ at slightly fatter tire. Mostly this could prove to be a trial and error situation unless you know a very understanding salvage yard that will allow you to test fit rims to find what you need or what will fit
