I have the factory caps
Bad pic of them.
I left them on and did "under the rail" spray on bedliner.
I figured the plastic would give a little extra protection over the spray on liner for the top of the bed sides. I like them so far.
I need to pull the driver side off and re-tape it because it is lifting a bit at 65+ mph. Bought truck July 07 with the bed caps on it. They are just double side taped on.
Tailgate is spray on liner.