Drilling for Fender Flares?? ((DELETE))

I'm considering putting some Bushwacker flares on my 2nd gen. It says they require drilling, but it seems like the only drill location would be on the front bumper section, which i'm not going to use since i have aftermarket bumpers. Do i have to drill to install the main part of the flare?
https://www.bushwacker.com/bushwacker-31920-02-pocket-style-fender-flares-front-and-rear

 

I don’t think so. If you just click on the instructions for install on the link you provided. It says no. They appear to be pretty good instructions with a method for attachment for after market bumpers also.

edit: after reading again, you may have to drill one or two per side.