Yes the 315/35/20s will fit thats what I have on my car , why are you going with such a big tire in the frt? If you have a 9" wide wheel you dont need to run such a big tire a 255/35/20 is what I have , you can run a 265/35/20 , but I think its really close to rubbing on the inside splash shields.
Im sure your looking at the overall diameter being the same 28.62 but thats pretty damn tall .
It will look better in my opinion with a bit shorter tire .
Pete