FWIW - Here's mine running craigslist 20's all around. Sorry don't have great pics as we've been working on it non stop. 20x9.5s in the back with 315/35/20s and 20X8.5s with 255/40/20s up front. With that wide a tire there is still a reasonable amount of sidewall in the back IMO and looks pretty good. The front sidewalls look to thin. It's at stock height so I think lowering an inch or two up there will make that look a lot better. Eventually I'll probably go 18's or 19's with a taller sidewall.
Personally I'd stay away from 17" wheels unless you know exactly what you want and don't think you will want to tweak the fit as there are just far fewer size options in 17s.
Also for what it's worth, it handles and rides really good with this setup considering its all stock.
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