You will have lots of trouble running that tire on a 95 Stang. The rim will fit, but you will rub with even a much more modest 30~35 series tire, much less a 45.
18' rims are perfect for ALL Stangs, IMO, and that is what I recommend. You can safely go 265/35/18's on 9's and 315/30/18's on 10.5's without any modifications to wheel wells.