Alright, I might be getting some rims off my friend, they are 20x9.5 all the way around, he had them on his '06 Acura TL, I know they will fit fine in the rear, but I'm kinda worried about the front , will they fit or am I going to have to roll/shave the front fenders?

 

I'm waiting for him to give me the rest of the info, (offset, lip size, etc.) will post up as soon as i get it ...

 

They might be ok depends on the tire I think. 9.5 width will fit almost positive.

 

Front will need a +45 and up to fit, plus a serious stretched tire and a Shaving...

 

9.5 will fit the front of the GS without many issues. Tire size will make or break the fitment. I have found +40 is about as high as you'd want to go.
+45 basically touches the suspension upright.