That's enough of a difference I'd recommend making the effort. I failed to do it quick enough on my last Jeep and regretted it when I got the speeding ticket. New to the 4Runner family, but with Jeeps it was easiest to take it to a dealer, pay the $135 license fee and them recalibrate everything...
I went with the same set-up as yours and after looking at the difference in overall diameter didn't think it was worth the effort. Have you used tiresize.com/calculator before?