Sn-95 conversion requires a 1/2 hub centric wheel spacer to fit a 15x4 prostar in the front (maximum motorsports has the best spacers imo) As long a you have the gt dia. rotors and not the cobra rotors in the rear a 15 will fit just fine. either 15x8w/ 5.5 " b.s. or 15x10 w/ 6.5" b.s. The 10" wheel will take some massaging to fit though
you probalby won't notice the differance between a 3.5 and 4 on the front. I know the 4" wheels are easier to find. You will have to remove the quad shocks in the rear and beat in the inner fender w/a hammer. it's that simple.
Tanks man. Your two for two on my questions now of things that ive long forgotten (took a several year haitius from stangs to persue other projects). I think im going to just PM you from now on lol