Just purchased 2022 Sierra 1500 Denali with factory spray on liner. Picking it up in a couple weeks. Buying a Retrax tonneau cover for the back. Instructions say to put drain tubes out the holes in the bed. Seen some videos of people who drill into the sidewalls. Are there any drain holes still visible with the sprayed on liner? Also might there be some on the floor up front to put the 3/8” hose into? Not sure about having to drill. Thanks for any help.