Tonneau Cover

I am thinking of buying Bak Industries R15120 tonneau cover. PLEASE, I need an advice only from those who 100% sure they are right.
For people using this on a shorted F150,I have the factory bed liner. The top of the bed rails have cover on them from the liner.Do I need to cut it?

Have you tried an F150 forum you might have better luck finding some one who used that combo there. Sorry I can not help.

What type of tonneau cover are planning to buy?