I am running 275/40R20's in the front on 20x9.5's. These are the Factory Replica wheels with 15mm offset in the front and 25mm in the rear. I originally ordered Wheel Replicas 9.5 front/11 rears, then bought my tires. Those wheels were on indefinite backorder so I switched to the FR's 9.5/10.5. I was very concerned about running 315/35's on them, but also didn't want to return the tires. They fit the wheel fine. I personally would not have liked the look of a 305/35's, which is what I would have bought if I knew I was getting 10.5's. The Nankangs have a very large rim protector lip on them which makes the tread and sidewall all flat with the rim. I don't feel like the 25mm offset is quite enough, but 28mm would be about the max. Conversely, if I would have gotten the 11" wheels I would have had to run 5mm wheel spacers. Space wise, you shouldn't have issues if you have a 2015+. Prior years have a smaller wheel well and a larger lip on the quarter panel.Pardon my ignorance, but you are running the 315/35R20 in the rear on the 10.5, what are you using up front?
Looking into to the FR 9.5 and 10.5 wheels, not sure what tire and size to go with in the rear. 315's seem to be the limit and some have to trim the inner liners.