Anybody know what I can use to fill those square holes in the bed rails? I plan on getting a low profile tonneau cover which doesn't come over those rails. Are there any types of caps or tie-down hooks, that I could install in there that are flush?

 

Wal-Mart did have the tie down caps that would fit. They would fold down flush when not in use.. Havn't checked in a while though..

 

They have a flip up type of hook and have a rubber piece that fills the hole when it is installed. Normally a chrome finish. You can also find them on some of our sponsors' pages.