Stock rear bump stop clearance?

[pjmoreland]

I don't know what to think about that drawing from the brochure. My tailgate is 23-3/4" high with a 6" drop. On top of that, my tires are smaller in diameter than the factory tires. It doesn't add up. Photos from the sales brochure make the space between the tires and fender wells look much larger than in that drawing.