If I remember correctly, these didn't require nutserts and the install was pretty simple. I used a jack, with a block of wood, to hold them in place. When you jack them up, do one side at a time, using the jack to make the slider snug up against the body. Applying a little bit of pressure on the rocker, use a spring loaded bunch to make a pilot mark on either outside (front or rear) hole. With the pilot mark in place, use a small drill bit first, to check that your centered. After that, use the correct size drill bit. Once you drill the first hole, I put a bolt and nut through it and snug that one as a way to hold the rocker in place.
With that done, I go to the opposite end, checking to make sure nothing moved, and do the same procedure. After that I move on to the other holes. Once all the holes have been drilled, I remove the rocker and put some touch up paint (or silicone) on the inside and outside of each hole to prevent future rust, then reassemble everything.
FWIW, if you're worried about the steps being slippery, you can always spray them with a rubber coating before you install them. Also, every rocker I've installed has required re-painting at some point. They get chipped with rocks and scratched by constantly stepping on them. As I said before, these aren't the best, but they're a decent product for the money that will provide solid rocker panel protection.
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