Installing a rear sway bar

I drive a 01 civic LX that don't have rear sway bar (the EX have a rear sway bar). I can install a sway bar off an EX to my civic without any risk? The car don't have the holes on the frame for the sway bar bolts, I can just drill the holes without any problem? Or an aftermarket or one off an RSX will be better?

I am thinking if the vehicle don't have a sway bar, and its frame wasn't make for a sway bar if I install one it can "hurt" the frame.