Our rock guard is mounded on chains attached to the frame just forward of the rear cap and with the lower edge just about 4 inches above the ground. Any lower and the guard will hit the ground more often and kick up road gravel/debris. We also have heavy mud flaps just aft of the dual rears.
Even with all that we still had some extensive dings on the Jeep from the road being just 'chipped' on the west entrance into Yellowstone. Having the rock guard WILL help though. That's the only time we have had any trouble. Good luck with the install. Bob
BTW, the material is what you are talking about...heavy rubber matting with a logo overlay.