Has anyone removed the plastic factory bed rail covers and sprayed bed liner over the rails? How do you fill the holes?

I have 2 trucks I plan on spraying, my '99 Superduty that will become my sons, and my '17 F150.

I plan to use this at home: Spray Bedliner - Trucks Floors Boats Trailers; Nationwide Dealers and DIY Kits

On my '99 Superduty the plastic bed rail caps don't look so great. I have in the past had a tool box that was screwed down with self tapping screws. I like the look of the over the rail bed liner, but I know if I take the plastic caps off I will have 2 rows of holes down each rail.

My question is how can I fill those holes (without welding them up), or otherwise prep them for spraying? I have heard of placing tape over the hole and spraying over the tape. I was wondering if anyone had tried this or had another suggestion.

 

I am about to have a liner sprayed in. I too have holes on the rails from the previous drop-in liner that some knucklehead screwed down. the guy at the place said that as long as they are small screw holes, he will just put tape under the rail, and the spray is so think it will fill in and you will never see them.

I have to wait for a week or so before I'll have the time to go have it done, I can let you know the results afterwards.