...My concern is water n grit getting caught between them n the rocker panels rusting them out.
Legitimate fear?
Certainly. But easily addressed as well. Like Slow Poke said, you seal them up along the top and the sides and you should not have any issue. I've had a different set on my '71 for 30 years and just took them off. I can show you a pic of the rocker panel, but suffice it to say it's still in pretty pristine shape from a rust standpoint.
I just used standard in-the-tube silicone sealer.
Has anyone actually set their rig down hard on a rock on those bolt-to-the-body "sliders". I can't imagine they protect anywhere near as well as ones mounted to the frame. They just seem like a lever to bend the rocker.
You're right about how it seems, but you'd be shocked how much force they can take when it's spread throughout the entire rocker through 1/4" plate steel. You can literally pivot your rig around a rock and the only damage is the scratches in the paint of the rocker guard.
You can certainly damage a rocker still of course, if you come down hard enough. But that's true of just about any style rocker guard. Especially the frame mounted ones that are cantilevered out from the frame.
There are some pretty stout frame mounted designs out there, but none that are off-the-shelf parts that I can think of. Maybe someone using that style has more feedback, but for most uses, the rocker mounted style, when done right, is VERY protective.
My buddy Rob (not that Rob haha) pivots on his WH rock sliders around trees. He used nut serts.
They seem uber strong the way they run all the way up the backside of the rocker sort of sandwiching the rocker. They are 3/16".
Thanks for the feedback. Good to know they're working out for him. I've seen some other nut-sert installations and they seem pretty stout.
The material is actually slightly thicker at 1/4" too. Not light, but very stout.
Paul