Longbox math correct. Which means, since backspace is all about whether rim will hit suspension or steering components, you need to be sure the extra .938 (15/16) won't hit anything, tire and wheel, front and rear, INCLUDING when fronts are turned stop to stop. Danger lurks. "Double, double toil and trouble" "Check the whole deal before you buy the wheel"
You said your truck is stock so we are all assuming the wheels are stock. Measurements are not that hard to do with tire on. Just need the correct length stick.
